#CONTENTSCUPS Software Administrators ManualCUPS Software Administrators Manual
CUPS-SAM-1.1.23
Easy Software Products
Copyright 1997-2005, All Rights Reserved
Table of Contents 
#1Preface #1_1System Overview #1_2Document Overview #1_3Notation Conventions #1_4Abbreviations #1_5Other References #OVERVIEW1 - Printing System Overview #2_1The Printing Problem #2_2The Technology #2_3Jobs #2_4Classes #2_5Filters #2_6Backends #2_7Printer Drivers #2_8Networking #BUILDING_INSTALLING2 - Building and Installing CUPS #3_1Installing a Source Distribution #REQUIREMENTSRequirements #COMPILINGCompiling CUPS #INSTALLINGInstalling the Software #RUNNINGRunning the Software #BINARYInstalling a Binary Distribution #PORTABLE-BINARYInstalling a Portable Distribution #RPM-BINARYInstalling an RPM Distribution #DPKG-BINARYInstalling an Debian Distribution #MANAGING_PRINTERS3 - Managing Printers #4_1The Basics #4_2Adding Your First Printer #4_2_1Adding Your First Printer from the Command-Line #ADD_WEBAdding Your First Printer from the Web #4_3Managing Printers from the Command-Line #4_3_1Adding and Modifying Printers #4_3_2Deleting Printers #4_3_3Setting the Default Printer #4_3_4Starting and Stopping Printers #4_3_5Accepting and Rejecting Print Jobs #4_3_6Setting Quotas on a Printer #4_3_7Restricting User Access to a Printer #4_4Managing Printers from the Web #PRINTER_CLASSES4 - Printer Classes #5_1The Basics #5_2Managing Printer Classes from the Command-Line #5_3Managing Printer Classes from the Web Interface #5_4Implicit Classes #CLIENT_SETUP5 - Client Setup #6_1The Basics #CLIENT_MANUALManual Configuration of Print Queues #CLIENT_SERVERSpecifying a Single Server for Printing #CLIENT_AUTOAutomatic Configuration of Print Queues #CLIENT_POLLSpecifying Multiple Servers for Printing #CLIENT_RELAYRelaying Printers to Other Clients #6_2Load Balancing and Failsafe Operation #PRINTING_MANAGEMENT6 - Printing System Management #7_1The Basics #RESTARTINGRestarting the CUPS Server #7_3Changing the Server Configuration #7_4Server Directives #AccessLogAccessLog #AllowAllow #AuthClassAuthClass #AuthGroupNameAuthGroupName #AuthTypeAuthType #AutoPurgeJobsAutoPurgeJobs #BrowseAddressBrowseAddress #BrowseAllowBrowseAllow #BrowseDenyBrowseDeny #BrowseIntervalBrowseInterval #BrowseOrderBrowseOrder #BrowsePollBrowsePoll #BrowsePortBrowsePort #BrowseProtocolsBrowseProtocols #BrowseRelayBrowseRelay #BrowseShortNamesBrowseShortNames #BrowseTimeoutBrowseTimeout #BrowsingBrowsing #ClassificationClassification #ClassifyOverrideClassifyOverride #ConfigFilePermConfigFilePerm #DataDirDataDir #DefaultCharsetDefaultCharset #DefaultLanguageDefaultLanguage #DenyDeny #DocumentRootDocumentRoot #EncryptionEncryption #ErrorLogErrorLog #FaxRetryIntervalFaxRetryInterval #FaxRetryLimitFaxRetryLimit #FileDeviceFileDevice #FilterLimitFilterLimit #FilterNiceFilterNice #FontPathFontPath #GroupGroup #HideImplicitMembersHideImplicitMembers #HostNameLookupsHostNameLookups #ImplicitAnyClassesImplicitAnyClasses #ImplicitClassesImplicitClasses #IncludeInclude #KeepAliveKeepAlive #KeepAliveTimeoutKeepAliveTimeout #LimitLimit #LimitExceptLimitExcept #LimitRequestBodyLimitRequestBody #ListenListen #LocationLocation #LogFilePermLogFilePerm #LogLevelLogLevel #MaxClientsMaxClients #MaxClientsPerHostMaxClientsPerHost #MaxCopiesMaxCopies #MaxJobsMaxJobs #MaxJobsPerPrinterMaxJobsPerPrinter #MaxJobsPerUserMaxJobsPerUser #MaxLogSizeMaxLogSize #MaxRequestSizeMaxRequestSize #OrderOrder #PageLogPageLog #PortPort #PreserveJobFilesPreserveJobFiles #PreserveJobHistoryPreserveJobHistory #PrintcapPrintcap #PrintcapFormatPrintcapFormat #PrintcapGUIPrintcapGUI #ReloadTimeoutReloadTimeout #RemoteRootRemoteRoot #RequestRootRequestRoot #RequireRequire #RIPCacheRIPCache #RootCertDurationRootCertDuration #RunAsUserRunAsUser #SatisfySatisfy #ServerAdminServerAdmin #ServerBinServerBin #ServerCertificateServerCertificate #ServerKeyServerKey #ServerNameServerName #ServerRootServerRoot #ServerTokensServerTokens #SSLListenSSLListen #SSLPortSSLPort #SystemGroupSystemGroup #TempDirTempDir #TimeoutTimeout #UserUser #7_5Changing the Client Configuration #7_6Client Directives #EncryptionEncryption #ServerNameServerName #7_7Changing the Printer Configuration #7_8Printer Directives #AcceptingAccepting #AllowUserAllowUser #DefaultPrinterDefaultPrinter #DenyUserDenyUser #DeviceURIDeviceURI #InfoInfo #JobSheetsJobSheets #KLimitKLimit #PrinterLocationLocation #PageLimitPageLimit #PrinterPrinter #QuotaPeriodQuotaPeriod #StateState #StateMessageStateMessage #7_9Changing the Classes Configuration #7_10Classes Directives #ClassAcceptingAccepting #ClassAllowUserAllowUser #ClassClass #DefaultClassDefaultClass #ClassDenyUserDenyUser #ClassInfoInfo #ClassJobSheetsJobSheets #ClassKLimitKLimit #ClassLocationLocation #ClassPageLimitPageLimit #ClassPrinterPrinter #ClassQuotaPeriodQuotaPeriod #ClassStateState #ClassStateMessageStateMessage #PRINTING_SECURITYPrinting System Security #CERTIFICATESAuthentication Using Certificates #7_11_2Using Basic Authentication #7_11_3Using Digest Authentication #7_11_4System and Group Authentication #PRINTER_ACCOUNTINGPrinter Accounting #7_12_1The access_log File #7_12_2The error_log File #7_12_3The page_log File #FILE_TYPING_FILTERINGFile Typing and Filtering #7_13_1mime.types #7_13_2mime.convs #7_13_3Adding Filetypes and Filters #7_13_4Printer Drivers and PPD Files #7_13_5Writing Your Own Filter or Printer Driver #PRINTING_OTHER7 - Printing with Other Systems #8_1The Basics #8_2Printing from LPD Clients #LPDPrinting to LPD Servers #8_4Printing from Mac OS 10.2 and Later Clients #8_5Printing from Mac OS 10.1 and Earlier Clients #8_5_1Columbia Appletalk Package (CAP) #8_5_2XINET KA/Spool #8_5_3Netatalk #8_6Printing to Mac OS 10.2 and Later Servers #8_7Printing to Mac OS 10.1 and Earlier Servers #8_8Printing from Windows Clients #8_8_1Exporting Printer Drivers #8_9Printing to Windows Servers #LICENSEA - Software License Agreement #9_1Common UNIX Printing System License Agreement #9_1_1Introduction #9_1_2License Exceptions #9_1_3Trademarks #9_1_4Binary Distribution Rights #9_1_5Support #9_2GNU GENERAL PUBLIC LICENSE #9_2_1Preamble #9_3GNU LIBRARY GENERAL PUBLIC LICENSE #9_3_1Preamble #COMMON_NETWORKB - Common Network Settings #10_1Configuring a Network Interface #10_1_1Configuring the IP Address Using ARP #10_1_2Configuring the IP Address Using RARP #10_1_3Configuring the IP Address Using BOOTP #10_2Verifying the Printer Connection #10_3Common Network Interface Settings #AXISConfiguring Axis Print Servers #LINKSYSConfiguring Linksys Print Servers #LPD_OPTIONSConfiguring LPD Printing Options #PRINTER_DRIVERSC - Printer Drivers #11_1Printer Drivers #DYMODYMO Label Printer #EPSON9EPSON 9-pin Dot Matrix #EPSON24EPSON 24-pin Dot Matrix #STCOLOREPSON Stylus Color #STPHOTOEPSON Stylus Photo #DESKJETHP DeskJet #LASERJETHP LaserJet #FILESD - List of Files #FAQE - Troubleshooting Common Problems #13_1My Applications Don't See the Available Printers #13_2CUPS Doesn't Recognize My Username or Password! #ALLOW_REMOTEI Can't Do Administration Tasks from Another
 Machine!
#13_4I Can't Do Administration Tasks from My Web Browser! #13_5Connection Refused Messages #13_6Write Error Messages Preface 
This software administrators manual provides printer administration
 information for the Common UNIX Printing System
TM ("CUPSTM
"), version 1.1.23.
System Overview 
CUPS provides a portable printing layer for UNIX®-based operating
 systems. It has been developed by 
http://www.easysw.comEasy
 Software Products
 to promote a standard printing solution for all
 UNIX vendors and users. CUPS provides the System V and Berkeley
 command-line interfaces.
CUPS uses the Internet Printing Protocol ("IPP") as the basis for
 managing print jobs and queues. The Line Printer Daemon ("LPD") Server
 Message Block ("SMB"), and AppSocket (a.k.a. JetDirect) protocols are
 also supported with reduced functionality. CUPS adds network printer
 browsing and PostScript Printer Description ("PPD") based printing
 options to support real-world printing under UNIX.
CUPS includes an image file RIP that supports printing of image files
 to non-PostScript printers. A customized version of GNU Ghostscript
 7.05 for CUPS called ESP Ghostscript is available separately to support
 printing of PostScript files within the CUPS driver framework. Sample
 drivers for Dymo, EPSON, HP, and OKIDATA printers are included that use
 these filters.
Drivers for thousands of printers are provided with our ESP Print Pro
 software, available at:
    
http://www.easysw.com/printpro/http://www.easysw.com/printpro/ CUPS is licensed under the GNU General Public License and GNU Library
 General Public License. Please contact Easy Software Products for
 commercial support and "binary distribution" rights.
Document Overview 
This software administrators manual is organized into the following
 sections:
#OVERVIEW1 - Printing System Overview #BUILDING_INSTALLING2 - Building and Installing CUPS #MANAGING_PRINTERS3 - Managing Printers #PRINTER_CLASSES4 - Printer Classes #CLIENT_SETUP5 - Client Setup #PRINTING_MANAGEMENT6 - Printing System Management #PRINTING_OTHER7 - Printing with Other Systems #LICENSEA - Software License Agreement #COMMON_NETWORKB - Common Network Settings #PRINTER_DRIVERSC - Printer Drivers #FILESD - List of Files #FAQE - Troubleshooting Common Problems Notation Conventions 
Various font and syntax conventions are used in this guide. Examples
 and their meanings and uses are explained below:
Example    Description  lpstat lpstat(1)    The names of commands;
 the first mention of a command or function in a chapter is followed by
 a manual page section number.
 /var /usr/share/cups/data/testprint.ps    File and directory names.
 Request ID is Printer-123    
Screen output.  lp -d printer filename ENTER    
Literal user input; special keys like ENTER are
 in ALL CAPS.
 12.3    Numbers in the text are
 written using the period (.) to indicate the decimal point.
Abbreviations 
 The following abbreviations are used throughout this manual:
kbKilobytes, or 1024 bytes
 MbMegabytes, or 1048576 bytes
 GbGigabytes, or 1073741824 bytes
 Other References 
CUPS Software Programmers ManualA programmer guide for interfacing with and/or extending the CUPS
 software.
 CUPS Software Users ManualAn end-user guide for using the CUPS software.
 1 - Printing System Overview 
This chapter provides an overview of how the Common UNIX Printing
 System works.
The Printing Problem 
For years the printing problem has plagued UNIX. Unlike
 Microsoft® Windows® or Mac OS, UNIX has no standard interface or system
 in place for supporting printers. Among the solutions currently
 available, the Berkeley and System V printing systems are the most
 prevalent.
These printing systems support line printers (text only) or
 PostScript printers (text and graphics), and with some coaxing they can
 be made to support a full range of printers and file formats. However,
 because each varient of the UNIX operating system uses a different
 printing system than the next developing printer drivers for a wide
 range of printers and operating systems is extremely difficult. That
 combined with the limited volume of customers for each UNIX varient has
 forced most printer vendors to give up supporting UNIX entirely.
CUPS is designed to eliminate the printing problem. One common
 printing system can be used by all UNIX varients to support the
 printing needs of users. Printer vendors can use its modular filter
 interface to develop a single driver program that supports a wide range
 of file formats with little or no effort. Since CUPS provides both the
 System V and Berkeley printing commands, users (and applications) can
 reap the benefits of this new technology with no changes.
The Technology 
CUPS is based upon an emerging Internet standard called the Internet
 Printing Protocol. IPP has been embraced by dozens of printer and
 printer server manufacturers and is supported by Microsoft Windows
 2000.
IPP defines a standard protocol for printing as well as managing
 print jobs and printer options like media size, resolution, and so
 forth. Like all IP-based protocols, IPP can be used locally or over the
 Internet to printers hundreds or thousands of miles away. Unlike other
 protocols, however, IPP also supports access control, authentication,
 and encryption, making it a much more capable and secure printing
 solution than older ones.
IPP is layered on top of the Hyper-Text Transport Protocol ("HTTP")
 which is the basis of web servers on the Internet. This allows users to
 view documentation, check status information on a printer or server,
 and manage their printers, classes, and jobs using their web browser.
CUPS provides a complete IPP/1.1 based printing system that provides
 Basic, Digest, and local certificate authentication and user, domain,
 or IP-based access control. TLS encryption will be available in future
 versions of CUPS.
Jobs 
Each file or set of files that is submitted for printing is called a job
. Jobs are identified by a unique number starting at 1 and are
 assigned to a particular destination, usually a printer. Jobs can also
 have options associated with them such as media size, number of copies,
 and priority.
Classes 
CUPS supports collections of printers known as classes. Jobs
 sent to a class are forwarded to the first available printer in the
 class.
Filters 
Filters allow a user or application to print many types of files
 without extra effort. Print jobs sent to a CUPS server are filtered
 before sending them to a printer. Some filters convert job files to
 different formats that the printer can understand. Others perform page
 selection and ordering tasks.
CUPS provides filters for printing many types of image files, HP-GL/2
 files, PDF files, and text files. CUPS also supplies PostScript and
 image file Raster Image Processor ("RIP") filters that convert
 PostScript or image files into bitmaps that can be sent to a raster
 printer.
Backends 
Backends perform the most important task of all - they send the
 filtered print data to the printer.
CUPS provides backends for printing over parallel, serial, and USB
 ports, and over the network via the IPP, JetDirect (AppSocket), and
 Line Printer Daemon ("LPD") protocols. Additional backends are
 available in network service packages such as the SMB backend included
 with the popular SAMBA software.
Backends are also used to determine the available devices. On startup
 each backend is asked for a list of devices it supports, and any
 information that is available. This allows the parallel backend to tell
 CUPS that an EPSON Stylus Color 600 printer is attached to parallel
 port 1, for example.
Printer Drivers 
Printer drivers in CUPS consist of one of more filters specific to a
 printer. CUPS includes sample printer drivers for Hewlett-Packard
 LaserJet and DeskJet printers and EPSON 9-pin, 24-pin, Stylus Color,
 and Stylus Photo printers. While these drivers do not generate optimal
 output for the different printer models, they do provide basic printing
 and demonstrate how you can write your own printer drivers and
 incorporate them into CUPS.
Networking 
Printers and classes on the local system are automatically shared
 with other systems on the network. This allows you to setup one system
 to print to a printer and use this system as a printer server or spool
 host for all of the others. Users may then select a local printer by
 name or a remote printer using "name@server".
CUPS also provides implicit classes, which are collections of
 printers and/or classes with the same name. This allows you to setup
 multiple servers pointing to the same physical network printer, for
 example, so that you aren't relying on a single system for printing.
 Because this also works with printer classes, you can setup multiple
 servers and printers and never worry about a single point of failure
 unless all of the printers and servers go down!
2 - Building and
 Installing CUPS
This chapter shows how to build and install the Common UNIX Printing
 System. If you are installing a binary distribution from the CUPS web
 site, proceed to the section titled, 
#BINARYInstalling a
 Binary Distribution
.
Installing a Source Distribution 
This section describes how to compile and install CUPS on your system
 from the source code.
Requirements 
You'll need ANSI-compliant C and C++ compilers to build CUPS on your
 system. As its name implies, CUPS is designed to run on the UNIX
 operating system, however the CUPS interface library and most of the
 filters and backends supplied with CUPS should also compile and run
 under Microsoft Windows.
For the image file filters and PostScript RIP, you'll need the JPEG,
 PNG, TIFF, and ZLIB libraries. CUPS will build without these, but with
 significantly reduced functionality. Easy Software Products maintains a
 mirror of the current versions of these libraries at:
ftp://ftp.easysw.com/pub/librariesftp://ftp.easysw.com/pub/libraries If you make changes to the man pages you'll need GNU groff or another
 nroff-like package. GNU groff is available from:
ftp://ftp.gnu.org/pub/groffftp://ftp.gnu.org/pub/groff The documentation is formatted using the HTMLDOC software. If you
 need to make changes you can get the HTMLDOC software from:
http://www.easysw.com/htmldochttp://www.easysw.com/htmldoc Finally, you'll need a make program that understands the
 
include directive - FreeBSD, NetBSD, and OpenBSD
 developers should use the 
gmake program.
Compiling CUPS 
CUPS uses GNU autoconf to configure the makefiles and source code for
 your system. Type the following command to configure CUPS for your
 system:
./configure ENTERThe default installation will put the CUPS software in the /etc,
 /usr, and /var directories on your system, which
 will overwrite any existing printing commands on your system. Use the 
--prefix
 option to install the CUPS software in another location:
./configure --prefix=/some/directory ENTERIf the PNG, JPEG, TIFF, and ZLIB libraries are not installed in a
 system default location (typically
 /usr/include and /usr/lib
) you'll need to set the CFLAGS, CXXFLAGS
, and LDFLAGS environment variables prior to
 running configure:
setenv CFLAGS "-I/some/directory" ENTERsetenv CXXFLAGS "-I/some/directory" ENTERsetenv LDFLAGS "-L/some/directory" ENTERsetenv DSOFLAGS "-L/some/directory" ENTER./configure ... ENTERor:
CFLAGS="-I/some/directory"; export CFLAGS ENTERCXXFLAGS="-I/some/directory"; export CXXFLAGS ENTERLDFLAGS="-L/some/directory"; export LDFLAGS ENTERDSOFLAGS="-L/some/directory"; export DSOFLAGS ENTER./configure ... ENTERTo enable support for encryption, you'll also want to add the
 "--enable-ssl" option:
./configure --enable-ssl
SSL and TLS support require the OpenSSL library, available at:
http://www.openssl.orghttp://www.openssl.org If the OpenSSL headers and libraries are not installed in the
 standard directories, use the 
--with-openssl-includes and --with-openssl-libs
 options:
./configure --enable-ssl \
    --with-openssl-includes=/foo/bar/include \
    --with-openssl-libs=/foo/bar/lib
Once you have configured things, just type:
make ENTERto build the software.
Installing the Software 
Use the "install" target to install the software:
make install ENTER  WARNING:Installing CUPS will overwrite your existing printing system. If you
 experience difficulties with the CUPS software and need to go back to
 your old printing system, you will need to reinstall the old printing
 system from your operating system CDs.
Running the Software 
Once you have installed the software you can start the CUPS server by
 typing:
/usr/sbin/cupsd ENTER Installing a Binary Distribution 
CUPS comes in a variety of binary distribution formats. Easy Software
 Products provides binaries in TAR format with installation and removal
 scripts ("portable" distributions), and in RPM and DPKG formats for Red
 Hat and Debian-based distributions. Portable distributions are
 available for all platforms, while the RPM and DPKG distributions are
 only available for Linux.
 WARNING:Installing CUPS will overwrite your existing printing system. If you
 experience difficulties with the CUPS software and need to go back to
 your old printing system, you will need to remove the CUPS software
 with the provided script and/or reinstall the old printing system from
 your operating system CDs.
Installing a Portable Distribution 
To install the CUPS software from a portable distribution you will
 need to be logged in as root; doing an 
su is good enough.
 Once you are the root user, run the installation script with:
./cups.install ENTERAfter asking you a few yes/no questions the CUPS software will be
 installed and the scheduler will be started automatically.
Installing an RPM Distribution 
To install the CUPS software from an RPM distribution you will need
 to be logged in as root; doing an 
su is good enough. Once
 you are the root user, run RPM with:
rpm -e lprrpm -i cups-1.1-linux-M.m.n-intel.rpm ENTERAfter a short delay the CUPS software will be installed and the
 scheduler will be started automatically.
Installing an Debian Distribution 
To install the CUPS software from a Debian distribution you will need
 to be logged in as root; doing an 
su is good enough. Once
 you are the root user, run dpkg with:
dpkg -i cups-1.1-linux-M.m.n-intel.deb ENTERAfter a short delay the CUPS software will be installed and the
 scheduler will be started automatically.
3 - Managing Printers 
This chapter describes how to add your first printer and how to
 manage your printers.
The Basics 
Each printer queue has a name associated with it; the printer name
 must start with any printable character except " ", "/", and "@". It
 can contain up to 127 letters, numbers, and the underscore (_). Case is
 not significant, e.g. "PRINTER", "Printer", and "printer" are
 considered to be the same name.
Printer queues also have a device associated with them. The device
 can be a parallel port, a network interface, and so forth. Devices
 within CUPS use Uniform Resource Identifiers ("URIs") which are a more
 general form of Uniform Resource Locators ("URLs") that are used in
 your web browser. For example, the first parallel port in Linux usually
 uses a device URI of 
parallel:/dev/lp1.
You can see a complete list of supported devices by running the lpinfo(8)
 command:
lpinfo -v ENTERnetwork socket
network http
network ipp
network lpd
direct parallel:/dev/lp1
serial serial:/dev/ttyS1?baud=115200
serial serial:/dev/ttyS2?baud=115200
direct usb:/dev/usb/lp0
network smb
The -v option specifies that you want a list of
 available devices. The first word in each line is the type of device
 (direct, file, network, or serial) and is followed by the device URI or
 method name for that device. File devices have device URIs of the form 
file:/directory/filename
 while network devices use the more
 familiar 
method://server or method://server/path format.
Finally, printer queues usually have a PostScript Printer Description
 ("PPD") file associated with them. PPD files describe the capabilities
 of each printer, the page sizes supported, etc., and are used for
 PostScript and non-PostScript printers. CUPS includes PPD files for HP
 LaserJet, HP DeskJet, EPSON 9-pin, EPSON 24-pin, and EPSON Stylus
 printers.
Adding Your First Printer 
CUPS provides two methods for adding printers: a command-line program
 called 
lpadmin(8) and a Web interface. The lpadmin command allows you to perform most printer administration tasks from
 the command-line and is located in
 /usr/sbin. The Web
 interface is located at:
http://localhost:631/adminhttp://localhost:631/admin and steps you through printer configuration. If you don't like
 command-line interfaces, try the 
#ADD_WEBWeb interface  instead.
Adding Your First Printer from the Command-Line 
Run the lpadmin command with the -p option
 to add a printer to CUPS:
/usr/sbin/lpadmin -p printer -E -v device -m ppd ENTERFor a HP DeskJet printer connected to the parallel port this would
 look like:
/usr/sbin/lpadmin -p DeskJet -E -v parallel:/dev/lp1 -m deskjet.ppd ENTERSimilarly, a HP LaserJet printer using a JetDirect network interface
 at IP address 11.22.33.44 would be added with the command:
/usr/sbin/lpadmin -p LaserJet -E -v socket://11.22.33.44 -m laserjet.ppd ENTERAs you can see, deskjet.ppd and laserjet.ppd are the PPD files for the HP DeskJet and HP LaserJet drivers included
 with CUPS. You'll find a complete list of PPD files and the printers
 they will work with in 
#PRINTER_DRIVERSAppendix C, "Printer
 Drivers"
.
For a dot matrix printer connected to the serial port, this might
 look like:
/usr/sbin/lpadmin -p DotMatrix -E -m epson9.ppd \
    -v serial:/dev/ttyS0?baud=9600+size=8+parity=none+flow=soft 
ENTERHere you specify the serial port (e.g. S0,S1, d0, d1), baud rate
 (e.g. 9600, 19200, 38400, 115200, etc.), number of bits, parity, and
 flow control. If you do not need flow control, delete the "+flow=soft"
 portion.
Adding Your First Printer from the Web 
The CUPS web server provides a user-friendly "wizard" interface for
 adding your printers. Rather than figuring out which device URI and PPD
 file to use, you can instead click on the appropriate listings and fill
 in some simple information. Enter the following URL in your web browser
 to begin:
http://localhost:631/adminhttp://localhost:631/admin Click on the Add Printer button to add a printer.
Managing Printers from the Command-Line 
The lpadmin command enables you to perform most printer
 administration tasks from the command-line. You'll find 
lpadmin in the
 /usr/sbin directory.
Adding and Modifying Printers 
Run the lpadmin command with the -p option
 to add or modify a printer:
/usr/sbin/lpadmin -p printer options ENTERThe options arguments can be any of the following:
-c classAdds the named printer to printer class class. If the
 class does not exist then it is created.
-i interfaceCopies the named interface script to the printer.
 Interface scripts are used by System V printer drivers. Since all
 filtering is disabled when using an interface script, scripts generally
 should not be used unless there is no other driver for a printer.
-m modelSpecifies a standard printer driver which is usually a PPD file.
 PPD's are usually stored under the
 /usr/share/cups/model/ directory structure. A list of all available models can be displayed
 using the 
lpinfo command with the -m option.
 A list of printer drivers included with CUPS can be found in 
#PRINTER_DRIVERSAppendix C, "Printer Drivers"
.-r classRemoves the named printer from printer class class. If
 the resulting class becomes empty then it is removed.
-v device-uriSets the device for communicating with the printer. If a job is
 currently printing on the named printer then the job will be restarted
 and sent to the new device.
-D infoProvides a textual description of the printer, e.g. "John's Personal
 Printer".
-EEnables the printer and accepts job. This option is equivalent to
 running the 
enable(1) and accept(8) commands
 on the printer.
-L locationProvides a textual location for the printer, e.g. "Computer Lab 5".-P ppd-fileSpecifies a local PPD file for the printer driver. Deleting Printers 
Run the lpadmin command with the -x option
 to delete a printer:
/usr/sbin/lpadmin -x printer ENTER Setting the Default Printer 
Run the lpadmin command with the -d option
 to set a default printer:
/usr/sbin/lpadmin -d printer ENTERThe default printer can be overridden by the user using the lpoptions(1)
 command.
Starting and Stopping Printers 
The enable and disable commands start and
 stop printer queues, respectively:
/usr/bin/enable printer ENTER/usr/bin/disable printer ENTERPrinters that are disabled may still accept jobs for printing, but
 won't actually print any files until they are restarted. This is useful
 if the printer malfunctions and you need time to correct the problem.
 Any queued jobs are printed after the printer is enabled (started).
Accepting and Rejecting Print Jobs 
The accept and reject commands accept and
 reject print jobs for the named printer, respectively:
/usr/sbin/accept printer ENTER/usr/sbin/reject printer ENTERAs noted above, a printer can be stopped but accepting new print
 jobs. A printer can also be rejecting new print jobs while it finishes
 those that have been queued. This is useful for when you must perform
 maintenance on the printer and will not have it available to users for
 a long period of time.
Setting Quotas on a Printer 
CUPS supports page and size-based quotas for each printer. The quotas
 are tracked individually for each user, but a single set of limits
 applies to all users for a partiuclar printer. For example, you can
 limit every user to 5 pages per day on an expensive printer, but you
 cannot limit every user except Johnny.
The job-k-limit, job-page-limit, and job-quota-peiod options determine whether and how quotas are enforced for a printer.
 The
 job-quota-period option determines the time interval for
 quota tracking. The interval is expressed in seconds, so a day is
 86,400, a week is 604,800 and a month is 2,592,000 seconds. The
 job-k-limit
 option specifies the job size limit in killobytes. The job-page-limit
 option specifies the number of pages limit.
For quotas to be enforced, the period and at least one of the limits
 must be set to a non-zero value. The following options will enable
 quotas:
/usr/sbin/lpadmin -p printer -o job-quota-period=604800 \
    -o job-k-limit=1024 
ENTER/usr/sbin/lpadmin -p printer -o job-quota-period=604800 \
    -o job-page-limit=100 
ENTEROr, you can combine all three options on the same line.
Restricting User Access to a Printer 
The -u option of the lpadmin command
 controls which users can print to a printer. The default configuration
 allows all users to print to a printer:
/usr/sbin/lpadmin -p printer -u allow:all ENTERCUPS supports allow and deny lists so that you can specify a list of
 users who are allowed to print or not allowed to print. Along with your
 list of users, you can specify whether they are allowed or not allowed
 to use the printer:
/usr/sbin/lpadmin -p printer -u allow:peter,paul,mary ENTERThis command allows peter, paul, and mary to print to the named
 printer, but all other users cannot print. The command:
/usr/sbin/lpadmin -p printer -u deny:peter,paul,mary ENTERhas the opposite effect. All users except peter, paul, and mary will
 be able to print to the named printer.
You can control access by UNIX groups as well by placing an "@"
 character before each group name. The command:
/usr/sbin/lpadmin -p printer -u allow:peter,paul,mary,@printgods ENTERallows the users peter, paul, and mary to print, as well as any user
 in the printgods group to print.
NOTE:The allow and deny options are not cummulative. That
 is, you must provide the complete list of users to allow or deny each
 time.
Also, CUPS only maintains one list of users - the list can allow or
 deny users from printing. If you specify an allow list and then specify
 a deny list, the deny list will replace the allow list - only one list
 is active at any time.
Managing Printers from the Web 
The Web interface is located at:
http://localhost:631/adminhttp://localhost:631/admin From there you can perform all printer management tasks with a few
 simple mouse clicks.
4 - Printer Classes 
This chapter describes what printer classes are and how to manage
 them.
The Basics 
CUPS provides collections of printers called printer classes.
 Jobs sent to a class are forwarded to the first available printer in
 the class. Classes can themselves be members of other classes, so it is
 possible for you to define very large, distributed printer classes for
 high-availability printing.
CUPS also supports implicit classes. Implicit classes work
 just like printer classes, but they are created automatically based
 upon the available printers and classes on the network. This allows you
 to setup multiple print servers with identical printer configurations
 and have the client machines send their print jobs to the first
 available server. If one or more servers go down, the jobs are
 automatically redirected to the servers that are running, providing
 fail-safe printing.
Managing Printer Classes from the Command-Line 
Run the lpadmin command with the -p and -c
 options to add a printer to a class:
/usr/sbin/lpadmin -p printer -c class ENTERThe class is created automatically if it doesn't exist. To
 remove a printer from a class use the 
-r option:
/usr/sbin/lpadmin -p printer -r class ENTERTo remove the entire class just use the -x option:
/usr/sbin/lpadmin -x class ENTER Managing Printer Classes from the Web Interface 
The Web interface is located at:
http://localhost:631/adminhttp://localhost:631/admin The Add Class and Modify Class interfaces
 provide a list of available printers; click on the printers of interest
 to add them to the class.
Implicit Classes 
A noted earlier, implicit classes are created automatically from the
 available network printers and classes. To disable this functionality,
 set the 
#ImplicitClassesImplicitClasses  directive to 
Off in the cupsd.conf file. You
 will find more information on doing this in 
#PRINTING_MANAGEMENTChapter 6, "Printing System Management"
.
5 - Client Setup 
This chapter discusses several ways to configure CUPS clients for
 printing.
The Basics 
A client is any machine that sends print jobs to another machine for
 final printing. Clients can also be servers if they communicate
 directly with any printers of their own.
CUPS supports several methods of configuring client machines:
#CLIENT_MANUALManual configuration of print queues. #CLIENT_SERVERSpecifying a single server for printing. #CLIENT_AUTOAutomatic configuration of print queues. #CLIENT_POLLSpecifying multiple servers for printing. #CLIENT_RELAYRelaying printers to other clients. Manual Configuration of Print Queues 
The most tedious method of configuring client machines is to
 configure each remote queue by hand using the 
lpadmin command:
lpadmin -p printer -E -v ipp://server/printers/printer ENTERThe printer name is the name of the printer on the
 server machine. The 
server name is the hostname or IP
 address of the server machine. Repeat the 
lpadmin command
 for each remote printer you wish to use.
 NOTE:Manual configuration of print queues is not recommended for large
 numbers of client machines because of the administration nightmare it
 creates. For busy networks, consider subnetting groups of clients and
 polling and relaying printer information instead.
Specifying a Single Server for Printing 
CUPS can be configured to run without a local spooler and send all
 jobs to a single server. However, if that server goes down then all
 printing will be disabled. Use this configuration only as absolutely
 needed.
The default server is normally "localhost". To override the default
 server create a file named
 /etc/cups/client.conf and add a
 line reading:
ServerName 
serverto the file. The server name can be the hostname or IP
 address of the default server.
The default server can also be customized on a per-user basis. To set
 a user-specific server create a file named
 ~/.cupsrc and add
 a line reading:
ServerName 
serverto the file. The server name can be the hostname or IP
 address of the default server.
Automatic Configuration of Print Queues 
CUPS supports automatic client configuration of printers on the same
 subnet. To configure printers on the same subnet,
 do nothing.
 Each client should see the available printers within 30 seconds
 automatically. The printer and class lists are updated automatically as
 printers and servers are added or removed.
If you want to see printers on other subnets as well, use the #BrowsePollBrowsePoll  directive as described next.
 NOTE:The #BrowseAddress BrowseAddress  directive
 enables broadcast traffic from your server. The default configuration
 braodcasts printer information every 30 seconds. Although this printer
 information does not use much bandwidth, typically about 80 bytes per
 printer, it can add up with large numbers of servers and printers.
Use the #BrowseIntervalBrowseInterval  and
 
#BrowseTimeoutBrowseTimeout  directives to
 tune the amount of data that is added to your network load. In
 addition, subnets can be used to minimize the amount of traffic that is
 carried by the "backbone" of your large network.
Specifying Multiple Servers for Printing 
If you have CUPS servers on different subnets, then you should
 configure CUPS to poll those servers. Polling provides the benefits of
 automatic configuration without significant configuration on the
 clients, and multiple clients on the same subnet can share the same
 configuration information.
Polling is enabled by specifying one or more #BrowsePollBrowsePoll
 directives in the /etc/cups/cupsd.conf file. For information on making these changes, see 
#PRINTING_MANAGEMENTChapter 6, "Printing System Management"
.
Multiple #BrowsePollBrowsePoll  lines can
 be used to poll multiple CUPS servers. To limit the amount of polling
 you do from client machines, you can have only one of the clients do
 the polling and relay that information to the others on the same subnet
 (described next).
Relaying Printers to Other Clients 
When you have clients and servers spread across multiple subnets, the
 polling method is inefficient. CUPS provides a 
#BrowseRelayBrowseRelay
 directive that enables a single client to relay
 (broadcast) the polled printer information to the local subnet.
For example, Server A and Server B are on subnet 1 and subnet 2,
 while the clients are on subnet 3. To provide printers to all of the
 clients in subnet 3, client C will be configured with the following
 directives in
 /etc/cups/cupsd.conf:
# Poll the two servers
BrowsePoll ServerA
BrowsePoll ServerB
# Relay the printers to the local subnet
BrowseRelay 127.0.0.1 192.168.3.255
The #BrowseRelayBrowseRelay  line
 specifies a source address and mask. Any browse packets coming from a
 matching address wil be sent to the given broadcast address. In this
 case, we want the packets from the local machine (127.0.0.1) relayed to
 the other clients.
As printers are found using polling, they are relayed from client C
 to the rest of the clients through a broadcast on subnet 3. The rest of
 the clients can use the standard
 cupsd.conf configuration.
The #BrowseRelayBrowseRelay  directive can
 also be used to relay browsing packets from one network interface to
 another. For example, if client C in the previous example had network
 interfaces attaches to both subnet 1 and subnet 2, it could use the 
#BrowseRelayBrowseRelay  directive exclusively:
# Relay the printers from subnet 1 and 2 to subnet 3
BrowseRelay 192.168.1 192.168.3.255
BrowseRelay 192.168.2 192.168.3.255
Load Balancing and Failsafe Operation 
When using server polling or broadcasting, CUPS clients can
 automatically merge identical printers on multiple servers into a
 single
 implicit class queue. Clients assume that printers with
 the same name on multiple servers are in fact the same printer or type
 of printer being served by multiple machines.
If you have two printers, LaserJet@ServerA and LaserJet@ServerB, a
 third implicit class called
 LaserJet will be created
 automatically on the client that refers to both printers. If the client
 also has a local printer with the name LaserJet and the 
#ImplicitAnyClassesImplicitAnyClasses  directive is enabled, then an
 implicit class named
 AnyLaserJet will be created instead.
 Otherwise, the local printer will prevent the creation of an implicit
 class, since CUPS will assume that the local printer will always be
 more available than a remote one.
The client will alternate between servers and automatically stop
 sending jobs to a server if it goes down, providing a load-balancing
 effect and fail-safe operation with automatic switchover.
 NOTE:Note that implicit classes ( #ImplicitClassesImplicitClasses
) are enabled and implicit "any" classes ( #ImplicitAnyClassesImplicitAnyClasses ) are disabled by default.
6 - Printing System
 Management
This chapter shows how you can configure the CUPS server.
The Basics 
Several text files are used to configure CUPS. All of the server
 configuration files are located in the
 /etc/cups directory:
classes.confThis file contains information on each printer class. Normally you
 manipulate this file using the 
lpadmin command or the Web
 interface.
 
client.confThis file provides the default server name for client machines. See #CLIENT_SETUPChapter 5, "Client Setup"  for more information.
 
cupsd.confThis file controls how the CUPS server (/usr/sbin/cupsd)
 operates and is normally edited by hand.
 
mime.convsThis file contains a list of standard file conversion filters and
 their costs. You normally do not edit this file.
 
mime.typesThis file contains a list of standard file formats and how to
 recognize them. You normally do not edit this file.
 
printers.confThis file contains information on each printer. Normally you
 manipulate this file using the 
lpadmin command or the Web
 Interface.
 Restarting the CUPS Server 
Once you have made a change to a configuration file you need to
 restart the CUPS server by sending it a 
HUP signal or
 using the supplied initialization script. The CUPS distributions
 install the script in the
 init.d directory with the name cups
. The location varies based upon the operating system:
/etc/software/init.d/cups restart ENTER/etc/rc.d/init.d/cups restart ENTER/etc/init.d/cups restart ENTER/sbin/init.d/cups restart ENTER Changing the Server Configuration 
The /etc/cups/cupsd.conf file contains configuration directives
 that control how the server functions. Each directive is
 listed on a line by itself followed by its value. Comments are
 introduced using the number sign ("#") character at the beginning of a
 line. Since the server configuration file consists of plain text, you
 can use your favorite text editor to make changes to it.
Server Directives 
The cupsd.conf file contains many directives that
 determine how the server operates:
#AccessLogAccessLog #AllowAllow #AuthClassAuthClass #AuthGroupNameAuthGroupName #AuthTypeAuthType #AutoPurgeJobsAutoPurgeJobs #BrowseAddressBrowseAddress #BrowseAllowBrowseAllow #BrowseDenyBrowseDeny #BrowseIntervalBrowseInterval #BrowseOrderBrowseOrder #BrowsePollBrowsePoll #BrowsePortBrowsePort #BrowseProtocolsBrowseProtocols #BrowseRelayBrowseRelay #BrowseShortNamesBrowseShortNames #BrowseTimeoutBrowseTimeout #BrowsingBrowsing #ClassificationClassification #ClassifyOverrideClassifyOverride #ConfigFilePermConfigFilePerm #DataDirDataDir #DefaultCharsetDefaultCharset #DefaultLanguageDefaultLanguage #DenyDeny #DocumentRootDocumentRoot #EncryptionEncryption #ErrorLogErrorLog #FaxRetryIntervalFaxRetryInterval     #FaxRetryLimitFaxRetryLimit #FileDeviceFileDevice #FilterLimitFilterLimit #FilterNiceFilterNice #FontPathFontPath #GroupGroup #HideImplicitMembersHideImplicitMembers #HostNameLookupsHostNameLookups #ImplicitAnyClassesImplicitAnyClasses #ImplicitClassesImplicitClasses #IncludeInclude #KeepAliveTimeoutKeepAliveTimeout #KeepAliveKeepAlive #LimitLimit #LimitExceptLimitExcept #LimitRequestBodyLimitRequestBody #ListenListen #LocationLocation #LogFilePermLogFilePerm #LogLevelLogLevel #MaxClientsMaxClients #MaxClientsPerHostMaxClientsPerHost #MaxCopiesMaxCopies #MaxJobsMaxJobs #MaxJobsPerPrinterMaxJobsPerPrinter #MaxJobsPerUserMaxJobsPerUser #MaxLogSizeMaxLogSize #MaxRequestSizeMaxRequestSize #OrderOrder     #PageLogPageLog #PortPort #PreserveJobFilesPreserveJobFiles #PreserveJobHistoryPreserveJobHistory #PrintcapPrintcap #PrintcapFormatPrintcapFormat #PrintcapGUIPrintcapGUI #ReloadTimeoutReloadTimeout #RemoteRootRemoteRoot #RequestRootRequestRoot #RequireRequire #RIPCacheRIPCache #RootCertDurationRootCertDuration #RunAsUserRunAsUser #SatisfySatisfy #ServerAdminServerAdmin #ServerBinServerBin #ServerCertificateServerCertificate #ServerKeyServerKey #ServerNameServerName #ServerRootServerRoot #ServerTokensServerTokens #SSLListenSSLListen #SSLPortSSLPort #SystemGroupSystemGroup #TempDirTempDir #TimeoutTimeout #UserUser AccessLog 
Examples
AccessLog /var/log/cups/access_log
AccessLog /var/log/cups/access_log-%s
AccessLog syslog
Description
The AccessLog directive sets the name of the access log
 file. If the filename is not absolute then it is assumed to be relative
 to the 
#ServerRootServerRoot  directory. The
 access log file is stored in "common log format" and can be used by any
 web access reporting tool to generate a report on CUPS server activity.
The server name can be included in the filename by using %s in the name.
The special name "syslog" can be used to send the access information
 to the system log instead of a plain file.
The default access log file is /var/log/cups/access_log.
Allow 
Examples
Allow from All
Allow from None
Allow from *.domain.com
Allow from .domain.com
Allow from host.domain.com
Allow from nnn.*
Allow from nnn.nnn.*
Allow from nnn.nnn.nnn.*
Allow from nnn.nnn.nnn.nnn
Allow from nnn.nnn.nnn.nnn/mm
Allow from nnn.nnn.nnn.nnn/mmm.mmm.mmm.mmm
Allow from @LOCAL
Allow from @IF(name)
Description
The Allow directive specifies a hostname, IP address, or
 network that is allowed access to the server. 
Allow directives are cummulative, so multiple 
Allow directives
 can be used to allow access for multiple hosts or networks. The 
/mm
 notation specifies a CIDR netmask:
mmnetmaskmm
netmask 0 0.0.0.0 8
255.0.0.0 1 128.0.0.0 16
255.255.0.0 2 192.0.0.0 24
255.255.255.0 ... ... 32
255.255.255.255 
The @LOCAL name will allow access from all local network
 interfaces, but not remote point-to-point interfaces. The 
@IF(name)
 name will allow access from the named interface.
The Allow directive must appear inside a #LocationLocation  directive.
AuthClass 
Examples
AuthClass Anonymous
AuthClass User
AuthClass System
AuthClass Group
Description
The AuthClass directive defines what level of
 authentication is required:
Anonymous - No authentication should be performed
 (default.)
User - A valid username and password is required.System - A valid username and password is required, and
 the username must belong to the "sys" group; this can be changed using
 the 
#SystemGroupSystemGroup  directive.Group - A valid username and password is required, and
 the username must belong to the group named by the 
AuthGroupName directive.
The AuthClass directive must appear inside a #LocationLocation  directive.
AuthGroupName 
Examples
AuthGroupName mygroup
AuthGroupName lp
Description
The AuthGroupName directive sets the group to use for Group
 authentication.
The AuthGroupName directive must appear inside a #LocationLocation  directive.
AuthType 
Examples
AuthType None
AuthType Basic
AuthType Digest
AuthType BasicDigest
Description
The AuthType directive defines the type of
 authentication to perform:
None - No authentication should be performed (default.)Basic - Basic authentication should be performed using
 the UNIX password and group files.
Digest - Digest authentication should be performed
 using the
 /etc/cups/passwd.md5 file.BasicDigest - Basic authentication should be performed
 using the
 /etc/cups/passwd.md5 file.When using Basic, Digest, or BasicDigest
 authentication, clients connecting through the localhost
 interface can also authenticate using #CERTIFICATEScertificates
.
The AuthType directive must appear inside a #LocationLocation  directive.
AutoPurgeJobs 
Examples
AutoPurgeJobs Yes
AutoPurgeJobs No
Description
The AutoPurgeJobs directive specifies whether or not to
 purge completed jobs once they are no longer required for quotas. This
 option has no effect if quotas are not enabled. The default setting is 
No
.
BrowseAddress 
Examples
BrowseAddress 255.255.255.255:631
BrowseAddress 192.0.2.255:631
BrowseAddress host.domain.com:631
BrowseAddress @LOCAL
BrowseAddress @IF(name)
Description
The BrowseAddress directive specifies an address to send
 browsing information to. Multiple 
BrowseAddress directives
 can be specified to send browsing information to different networks or
 systems.
The @LOCAL name will broadcast printer information to
 all local interfaces. The 
@IF(name) name will broadcast to
 the named interface.
No browse addresses are set by default.
 NOTE:If you are using HP-UX 10.20 and a subnet that is not 24, 16, or 8
 bits, printer browsing (and in fact all broadcast reception) will not
 work. This problem appears to be fixed in HP-UX 11.0.
BrowseAllow 
Examples
BrowseAllow from all
BrowseAllow from none
BrowseAllow from 192.0.2
BrowseAllow from 192.0.2.0/24
BrowseAllow from 192.0.2.0/255.255.255.0
BrowseAllow from *.domain.com
BrowseAllow from @LOCAL
BrowseAllow from @IF(name)
Description
The BrowseAllow directive specifies a system or network
 to accept browse packets from. The default is to accept browse packets
 from all hosts.
Host and domain name matching require that you enable the #HostNameLookupsHostNameLookups  directive.
IP address matching supports exact matches, partial addresses that
 match networks using netmasks of 255.0.0.0, 255.255.0.0, and
 255.255.255.0, or network addresses using the specified netmask or bit
 count.
The @LOCAL name will allow browse data from all local
 network interfaces, but not remote point-to-point interfaces. The 
@IF(name)
 name will allow browse data from the named interface.
BrowseDeny 
Examples
BrowseDeny from all
BrowseDeny from none
BrowseDeny from 192.0.2
BrowseDeny from 192.0.2.0/24
BrowseDeny from 192.0.2.0/255.255.255.0
BrowseDeny from *.domain.com
BrowseDeny from @LOCAL
BrowseDeny from @IF(name)
Description
The BrowseDeny directive specifies a system or network
 to reject browse packets from. The default is to deny browse packets
 from no hosts.
Host and domain name matching require that you enable the #HostNameLookupsHostNameLookups  directive.
IP address matching supports exact matches, partial addresses that
 match networks using netmasks of 255.0.0.0, 255.255.0.0, and
 255.255.255.0, or network addresses using the specified netmask or bit
 count.
The @LOCAL name will block browse data from all local
 network interfaces, but not remote point-to-point interfaces. The 
@IF(name)
 name will block browse data from the named interface.
BrowseInterval 
Examples
BrowseInterval 0
BrowseInterval 30
Description
The BrowseInterval directive specifies the maximum
 amount of time between browsing updates. Specifying a value of 0
 seconds disables outgoing browse updates but allows a server to receive
 printer information from other hosts.
The BrowseInterval value should always be less than the #BrowseTimeoutBrowseTimeout  value. Otherwise
 printers and classes will disappear from client systems between
 updates.
BrowseOrder 
Examples
BrowseOrder allow,deny
BrowseOrder deny,allow
Description
The BrowseOrder directive specifies the order of
 allow/deny processing. The default order is 
deny,allow:
allow,deny - Browse packets are accepted unless
 specifically denied.
deny,allow - Browse packets are rejected unless
 specifically allowed.
BrowsePoll 
Examples
BrowsePoll 192.0.2.2:631
BrowsePoll host.domain.com:631
Description
The BrowsePoll directive polls a server for available
 printers once every 
#BrowseIntervalBrowseInterval  seconds. Multiple BrowsePoll directives can be
 specified to poll multiple servers.
If BrowseInterval is set to 0 then the server is polled
 once every 30 seconds.
BrowsePort 
Examples
BrowsePort 631
BrowsePort 9999
Description
The BrowsePort directive specifies the UDP port number
 used for browse packets. The default port number is 631.
 NOTE:You must set the BrowsePort to the same value on all of
 the systems that you want to see.
BrowseProtocols 
Examples
BrowseProtocols CUPS
BrowseProtocols SLP
BrowseProtocols CUPS SLP
BrowseProtocols all
Description
The BrowseProtocols directive specifies the protocols to
 use when collecting and distributing shared printers on the local
 network. The default protocol is 
CUPS, which is a
 broadcast-based protocol.
 NOTE:When using the SLP protocol, you must have at least one
 Directory Agent (DA) server on your network. Otherwise the CUPS
 scheduler (
cupsd) will not respond to client requests for
 several seconds while polling the network.
BrowseRelay 
Examples
BrowseRelay 193.0.2.1 192.0.2.255
BrowseRelay 193.0.2.0/255.255.255.0 192.0.2.255
BrowseRelay 193.0.2.0/24 192.0.2.255
BrowseRelay *.domain.com 192.0.2.255
BrowseRelay host.domain.com 192.0.2.255
Description
The BrowseRelay directive specifies source and
 destination addresses for relaying browsing information from one host
 or network to another. Multiple 
BrowseRelay directives can
 be specified as needed.
BrowseRelay is typically used on systems that bridge
 multiple subnets using one or more network interfaces. It can also be
 used to relay printer information from polled servers with the line:
BrowseRelay 127.0.0.1 255.255.255.255
This effectively provides access to printers on a WAN for all clients
 on the LAN(s).
BrowseShortNames 
Examples
BrowseShortNames Yes
BrowseShortNames No
Description
The BrowseShortNames directive specifies whether or not
 short names are used for remote printers when possible. Short names are
 just the remote printer name, without the server ("printer"). If more
 than one remote printer is detected with the same name, the printers
 will have long names ("printer@server1", "printer@server2".)
The default value for this option is Yes.
BrowseTimeout 
Examples
BrowseTimeout 300
BrowseTimeout 60
Description
The BrowseTimeout directive sets the timeout for printer
 or class information that is received in browse packets. Once a printer
 or class times out it is removed from the list of available
 destinations.
The BrowseTimeout value should always be greater than
 the 
#BrowseIntervalBrowseInterval  value.
 Otherwise printers and classes will disappear from client systems
 between updates.
Browsing 
Examples
Browsing On
Browsing Off
Description
The Browsing directive controls whether or not network
 printer browsing is enabled. The default setting is 
On.
 NOTE:If you are using HP-UX 10.20 and a subnet that is not 24, 16, or 8
 bits, printer browsing (and in fact all broadcast reception) will not
 work. This problem appears to be fixed in HP-UX 11.0.
Classification 
Examples
Classification
Classification classified
Classification confidential
Classification secret
Classification topsecret
Classification unclassified
Description
The Classification directive sets the classification
 level on the server. When this option is set, at least one of the
 banner pages is forced to the classification level, and the
 classification is placed on each page of output. The default is no
 classification level.
ClassifyOverride 
Examples
ClassifyOverride Yes
ClassifyOverride No
Description
The ClassifyOverride directive specifies whether users
 can override the default classification level on the server. When the
 server classification is set, users can change the classification using
 the 
job-sheets option and can choose to only print one
 security banner before or after the job. If the 
job-sheets option is set to 
none then the server default
 classification is used.
The default is to not allow classification overrides.
ConfigFilePerm 
Examples
ConfigFilePerm 0644
ConfigFilePerm 0600
Description
The ConfigFilePerm directive specifies the permissions
 to use when writing configuration files. The default is 0600.
DataDir 
Examples
DataDir /usr/share/cups
Description
The DataDir directive sets the directory to use for data
 files.
DefaultCharset 
Examples
DefaultCharset utf-8
DefaultCharset iso-8859-1
DefaultCharset windows-1251
Description
The DefaultCharset directive sets the default character
 set to use for client connections. The default character set is 
utf-8
 but is overridden by the character set for the language
 specified by the client or the 
DefaultLanguage directive.
DefaultLanguage 
Examples
DefaultLanguage de
DefaultLanguage en
DefaultLanguage es
DefaultLanguage fr
DefaultLanguage it
Description
The DefaultLanguage directive specifies the default
 language to use for client connections. Setting the default language
 also sets the default character set if a language localization file
 exists for it. The default language is "en" for English.
Deny 
Examples
Deny from All
Deny from None
Deny from *.domain.com
Deny from .domain.com
Deny from host.domain.com
Deny from nnn.*
Deny from nnn.nnn.*
Deny from nnn.nnn.nnn.*
Deny from nnn.nnn.nnn.nnn
Deny from nnn.nnn.nnn.nnn/mm
Deny from nnn.nnn.nnn.nnn/mmm.mmm.mmm.mmm
Deny from @LOCAL
Deny from @IF(name)
Description
The Deny directive specifies a hostname, IP address, or
 network that is allowed access to the server. 
Deny directives are cummulative, so multiple 
Deny directives
 can be used to allow access for multiple hosts or networks. The 
/mm
 notation specifies a CIDR netmask:
mmnetmaskmm
netmask 0 0.0.0.0 8
255.0.0.0 1 128.0.0.0 16
255.255.0.0 2 192.0.0.0 24
255.255.255.0 ... ... 32
255.255.255.255 
The @LOCAL name will deny access from all local network
 interfaces, but not remote point-to-point interfaces. The 
@IF(name)
 name will deny access from the named interface.
The Deny directive must appear inside a #LocationLocation  directive.
DocumentRoot 
Examples
DocumentRoot /usr/share/doc/cups
DocumentRoot /foo/bar/doc/cups
Description
The DocumentRoot directive specifies the location of web
 content for the HTTP server in CUPS. If an absolute path is not
 specified then it is assumed to be relative to the 
#ServerRootServerRoot  directory. The default directory is /usr/share/doc/cups
.
Documents are first looked up in a sub-directory for the primary
 language requested by the client (e.g.
 /usr/share/doc/cups/fr/...) and then directly under the 
DocumentRoot directory (e.g. /usr/share/doc/cups/...
), so it is possible to localize the web
 content by providing subdirectories for each language needed.
Encryption 
Examples
Encryption Never
Encryption IfRequested
Encryption Required
Description
The Encryption directive must appear instead a #LocationLocation  section and specifies the encryption settings
 for that location. The default setting is 
IfRequested for
 all locations.
ErrorLog 
Examples
ErrorLog /var/log/cups/error_log
ErrorLog /var/log/cups/error_log-%s
ErrorLog syslog
Description
The ErrorLog directive sets the name of the error log
 file. If the filename is not absolute then it is assumed to be relative
 to the 
#ServerRootServerRoot  directory. The
 default error log file is
 /var/log/cups/error_log.
The server name can be included in the filename by using %s in the name.
The special name "syslog" can be used to send the error information
 to the system log instead of a plain file.
FaxRetryInterval 
Examples
FaxRetryInterval 300
FaxRetryInterval 30
Description
The FaxRetryInterval directive determines how often fax
 print jobs are retried when the backend is unable to send the fax. The
 value is the number of seconds between tries.
The default setting is 300 seconds.
FaxRetryLimit 
Examples
FaxRetryLimit 5
FaxRetryLimit 100
Description
The FaxRetryLimit directive determines how many times a
 fax job is retried before it is canceled.
The default setting is 5.
FileDevice 
Examples
FileDevice Yes
FileDevice No
Description
The FileDevice directive determines whether the
 scheduler allows new printers to be added using device URIs of the form
 
file:/filename. File devices are most often used to test
 new printer drivers and do no support raw file printing.
The default setting is No.
 Note:File devices are managed by the scheduler. Since the scheduler
 normally runs as the root user, file devices can be used to overwrite
 system files and potentially gain unauthorized access to the system. If
 you must create printers using file devices, we recommend that you set
 the 
FileDevice directive to Yes for only as
 long as you need to add the printers to the system, and then reset the
 directive to 
No.
FilterLimit 
Examples
FilterLimit 0
FilterLimit 200
FilterLimit 1000
Description
The FilterLimit directive sets the maximum cost of all
 running job filters. It can be used to limit the number of filter
 programs that are run on a server to minimize disk, memory, and CPU
 resource problems. A limit of 0 disables filter limiting.
An average print to a non-PostScript printer needs a filter limit of
 about 200. A PostScript printer needs about half that (100). Setting
 the limit below these thresholds will effectively limit the scheduler
 to printing a single job at any time.
The default limit is 0.
FilterNice 
Examples
FilterNice 0
FilterNice 39
FilterNice -10
Description
The FilterNice directive sets the scheduling priority of
 job filters. Values larger than 0 give filters a lower priority while
 values smaller than 0 give filters a higher priority. The 
FilterNice
 value does not affect the priority of job backends.
The default priority is 0.
FontPath 
Examples
FontPath /foo/bar/fonts
FontPath /usr/share/cups/fonts:/foo/bar/fonts
Description
The FontPath directive specifies the font path to use
 when searching for fonts. The default font path is 
/usr/share/cups/fonts
.
Group 
Examples
Group sys
Group system
Group root
Description
The Group directive specifies the UNIX group that filter
 and CGI programs run as. The default group is 
sys, system
, or root depending on the operating system.
HideImplicitMembers 
Examples
HideImplicitMembers Yes
HideImplicitMembers No
Description
The HideImplicitMembers directive controls whether the
 individual printers in an implicit class are shown to the user. The
 default is 
No.
#ImplicitClassesImplicitClasses  must be
 enabled for this directive to have any effect.
HostNameLookups 
Examples
HostNameLookups On
HostNameLookups Off
HostNameLookups Double
Description
The HostNameLookups directive controls whether or not
 CUPS looks up the hostname for connecting clients. The 
Double setting causes CUPS to verify that the hostname resolved from the
 address matches one of the addresses returned for that hostname. 
Double
 lookups also prevent clients with unregistered addresses
 from connecting to your server. The default is 
Off to
 avoid the potential server performance problems with hostname lookups.
 Set this option to 
On or Double only if
 absolutely required.
ImplicitAnyClasses 
Examples
ImplicitAnyClasses On
ImplicitAnyClasses Off
Description
The ImplicitAnyClasses directive controls whether
 implicit classes for local and remote printers are created with the
 name 
AnyPrinter. The default setting is Off.
#ImplicitClassesImplicitClasses  must be
 enabled for this directive to have any effect.
ImplicitClasses 
Examples
ImplicitClasses On
ImplicitClasses Off
Description
The ImplicitClasses directive controls whether implicit
 classes are created based upon the available network printers and
 classes. The default setting is 
On but is automatically
 turned 
Off if #BrowsingBrowsing  is turned 
Off.
Include 
Examples
Include filename
Include /foo/bar/filename
Description
The Include directive includes the named file in the cupsd.conf
 file. If no leading path is provided, the file is
 assumed to be relative to the 
#ServerRootServerRoot  directory.
KeepAlive 
Examples
KeepAlive On
KeepAlive Off
Description
The KeepAlive directive controls whether or not to
 support persistent HTTP connections. The default is 
On.
HTTP/1.1 clients automatically support persistent connections, while
 HTTP/1.0 clients must specifically request them using the 
Keep-Alive
 attribute in the Connection: field of
 each request.
KeepAliveTimeout 
Examples
KeepAliveTimeout 60
KeepAliveTimeout 30
Description
The KeepAliveTimeout directive controls how long a
 persistent HTTP connection will remain open after the last request. The
 default is 60 seconds.
Limit 
Examples
<Limit GET POST>
...
</Limit>
<Limit ALL>
...
</Limit>
Description
The Limit directive groups access control directives for
 specific types of HTTP requests and must appear inside a 
#LocationLocation  section. Access can be limited for individual
 request types (
DELETE, GET, HEAD, 
OPTIONS, POST, PUT, and TRACE
) or for all request types (ALL). The request
 type names are case-sensitive for compatibility with Apache.
LimitExcept 
Examples
<LimitExcept GET POST>
...
</LimitExcept>
Description
The LimitExcept directive groups access control
 directives for specific types of HTTP requests and must appear inside a
 
#LocationLocation  section. Unlike the #LimitLimit  directive, LimitExcept restricts
 access for all requests
 except those listed on the LimitExcept
 line.
LimitRequestBody 
Examples
LimitRequestBody 10485760
LimitRequestBody 10m
LimitRequestBody 0
Description
The LimitRequestBody directive controls the maximum size
 of print files, IPP requests, and HTML form data in HTTP POST requests.
 The default limit is 0 which disables the limit check.
Also see the identical #MaxRequestSizeMaxRequestSize  directive.
Listen 
Examples
Listen 127.0.0.1:631
Listen 192.0.2.1:631
Description
The Listen directive specifies a network address and
 port to listen for connections. Multiple 
Listen directives
 can be provided to listen on multiple addresses.
The Listen directive is similar to the #PortPort
 directive but allows you to restrict access to specific
 interfaces or networks.
Location 
Examples
<Location />
...
</Location>
<Location /admin>
...
</Location>
<Location /printers>
...
</Location>
<Location /printers/name>
...
</Location>
<Location /classes>
...
</Location>
<Location /classes/name>
...
</Location>
Description
The Location directive specifies access control and
 authentication options for the specified HTTP resource or path. The 
#AllowAllow , #AuthClassAuthClass ,
 
#AuthGroupNameAuthGroupName , #AuthTypeAuthType , #DenyDeny , #EncryptionEncryption , #LimitLimit , #LimitExceptLimitExcept , #OrderOrder , #RequireRequire , and #SatisfySatisfy
 directives may all appear inside a location.
Locations on the Server.LocationDescription / The path for all get operations (get-printers,
 get-jobs, etc.)
/admin The path for all administration operations
 (add-printer, delete-printer, start-printer, etc.)
/admin/conf The path for access to the CUPS
 configuration files (cupsd.conf, client.conf, etc.)
/classes The path for all classes /classes/name The resource for class name /jobs The path for all jobs (hold-job, release-job,
 etc.)
/jobs/id The resource for job id /printers The path for all printers /printers/name The path for printer name /printers/name.ppd The PPD file path for printer name
Note that more specific resources override the less specific ones. So
 the directives inside the 
/printers/name location will
 override ones from 
/printers. Directives inside /printers
 will override ones from /.   None of the
 directives are inherited. More information can be found in section 
#PRINTING_SECURITY"Printing System Security"
.
LogFilePerm 
Examples
LogFilePerm 0644
LogFilePerm 0600
Description
The LogFilePerm directive specifies the permissions to
 use when writing configuration files. The default is 0644.
LogLevel 
Examples
LogLevel none
LogLevel emerg
LogLevel alert
LogLevel crit
LogLevel error
LogLevel warn
LogLevel notice
LogLevel info
LogLevel debug
LogLevel debug2
Description
The LogLevel directive specifies the level of logging
 for the 
#ErrorLogErrorLog  file. The
 following values are recognized (each level logs everything under the
 preceding levels):
none - Log nothing.emerg - Log emergency conditions that prevent the
 server from running.
alert - Log alerts that must be handled immediately.crit - Log critical errors that don't prevent the
 server from running.
error - Log general errors.warn - Log errors and warnings.notice - Log temporary error conditions.info - Log all requests and state changes (default).debug - Log basic debugging information.debug2 - Log all debugging information. MaxClients 
Examples
MaxClients 100
MaxClients 1024
Description
The MaxClients directive controls the maximum number of
 simultaneous clients that will be allowed by the server. The default is
 100 clients.
 NOTE:Since each print job requires a file descriptor for the status pipe,
 the CUPS server internally limits the 
MaxClients value to
 1/3 of the available file descriptors to avoid possible problems when
 printing large numbers of jobs.
MaxClientsPerHost 
Examples
MaxClientsPerHost 0
MaxClientsPerHost 10
Description
The MaxClientsPerHost directive controls the maximum
 number of simultaneous clients that will be allowed from a single host
 by the server. The default is the 
MaxClients value. A
 value of 0 uses the automatic setting based on the 
MaxClients value.
This directive provides a small measure of protection against Denial
 of Service attacks from a single host.
MaxCopies 
Examples
MaxCopies 100
MaxCopies 65535
Description
The MaxCopies directive controls the maximum number of
 copies that a user can print of a job. The default is 100 copies.
 NOTE:Most HP PCL laser printers internally limit the number of copies to
 100.
MaxJobs 
Examples
MaxJobs 100
MaxJobs 9999
MaxJobs 0
Description
The MaxJobs directive controls the maximum number of
 jobs that are kept in memory. Once the number of jobs reaches the
 limit, the oldest completed job is automatically purged from the system
 to make room for the new one. If all of the known jobs are still
 pending or active then the new job will be rejected.
Setting the maximum to 0 disables this functionality. The default
 setting is 500.
MaxJobsPerPrinter 
Examples
MaxJobsPerPrinter 100
MaxJobsPerPrinter 9999
MaxJobsPerPrinter 0
Description
The MaxJobsPerPrinter directive controls the maximum
 number of active jobs that are allowed for each printer or class. Once
 a printer or class reaches the limit, new jobs will be rejected until
 one of the active jobs is completed, stopped, aborted, or cancelled.
Setting the maximum to 0 disables this functionality. The default
 setting is 0.
MaxJobsPerUser 
Examples
MaxJobsPerUser 100
MaxJobsPerUser 9999
MaxJobsPerUser 0
Description
The MaxJobsPerUser directive controls the maximum number
 of active jobs that are allowed for each user. Once a user reaches the
 limit, new jobs will be rejected until one of the active jobs is
 completed, stopped, aborted, or cancelled.
Setting the maximum to 0 disables this functionality. The default
 setting is 0.
MaxLogSize 
Examples
MaxLogSize 1048576
MaxLogSize 1m
MaxLogSize 0
Description
The MaxLogSize directive controls the maximum size of
 each log file. Once a log file reaches or exceeds the maximum size it
 is closed and renamed to
 filename.O. This allows you to
 rotate the logs automatically. The default size is 1048576 bytes (1MB).
Setting the maximum size to 0 disables log rotation.
MaxRequestSize 
Examples
MaxRequestSize 10485760
MaxRequestSize 10m
MaxRequestSize 0
Description
The MaxRequestSize directive controls the maximum size
 of print files, IPP requests, and HTML form data in HTTP POST requests.
 The default limit is 0 which disables the limit check.
Also see the identical #LimitRequestBodyLimitRequestBody
 directive.
Order 
Examples
Order Allow,Deny
Order Deny,Allow
Description
The Order directive defines the default access control.
 The following values are supported:
Allow,Deny - Allow requests from all systems except for those listed in a 
Deny directive.Deny,Allow - Allow requests only from those listed in
 an 
Allow directive.The Order directive must appear inside a #LocationLocation  directive.
PageLog 
Examples
PageLog /var/log/cups/page_log
PageLog /var/log/cups/page_log-%s
PageLog syslog
Description
The PageLog directive sets the name of the page log
 file. If the filename is not absolute then it is assumed to be relative
 to the 
#ServerRootServerRoot  directory. The
 default page log file is
 /var/log/cups/page_log.
The server name can be included in the filename by using %s in the name.
The special name "syslog" can be used to send the page information to
 the system log instead of a plain file.
Port 
Examples
Port 631
Port 80
Description
The Port directive specifies a port to listen on.
 Multiple 
Port lines can be specified to listen on multiple
 ports. The 
Port directive is equivalent to "Listen
 *:nnn
". The default port is 631.
PreserveJobFiles 
Examples
PreserveJobFiles On
PreserveJobFiles Off
Description
The PreserveJobFiles directive controls whether the
 document files of completed, cancelled, or aborted print jobs are
 stored on disk.
A value of On preserves job files until the
 administrator purges them with the 
cancel command. Jobs
 can be restarted (and reprinted) as desired until they are purged.
A value of Off (the default) removes the job files as
 soon as each job is completed, cancelled, or aborted.
PreserveJobHistory 
Examples
PreserveJobHistory On
PreserveJobHistory Off
Description
The PreserveJobHistory directive controls whether the
 history of completed, cancelled, or aborted print jobs is stored on
 disk.
A value of On (the default) preserves job information
 until the administrator purges it with the 
cancel command.
A value of Off removes the job information as soon as
 each job is completed, cancelled, or aborted.
Printcap 
Examples
Printcap
Printcap /etc/printcap
Printcap /etc/printers.conf
Description
The Printcap directive controls whether or not a
 printcap file is automatically generated and updated with a list of
 available printers. If specified with no value, then no printcap file
 will be generated. The default is to generate a file named
 /etc/printcap
.
When a filename is specified (e.g. /etc/printcap), the
 printcap file is written whenever a printer is added or removed. The
 printcap file can then be used by applications that are hardcoded to
 look at the printcap file for the available printers.
PrintcapFormat 
Examples
PrintcapFormat BSD
PrintcapFormat Solaris
Description
The PrintcapFormat directive controls the output format
 of the printcap file. The default is to generate a BSD printcap file.
PrintcapGUI 
Example
PrintcapGUI /usr/bin/glpoptions
Description
The PrintcapGUI directive sets the program to use when
 displaying an option panel from an IRIX application that uses the
 Impressario print API. The default program is the ESP Print Pro
 "glpoptions" GUI.
The program must accept the -d option to specify a
 printer and the 
-o option to specify one or more options.
 After allowing the user to select/change options, the program must then
 write the list of printing options without the 
-o to the
 standard output.
ReloadTimeout 
Examples
ReloadTimeout 60
ReloadTimeout 3600
ReloadTimeout 0
Description
The ReloadTimeout directive sets how long the scheduler
 waits for jobs to complete before reloading the server configuration.
 The default timeout is 60 seconds.
RemoteRoot 
Examples
RemoteRoot remroot
RemoteRoot root
Description
The RemoteRoot directive sets the username for
 unauthenticated root requests from remote hosts. The default username
 is
 remroot. Setting RemoteRoot to root effectively disables this security mechanism.
RequestRoot 
Examples
RequestRoot /var/spool/cups
RequestRoot /foo/bar/spool/cups
Description
The RequestRoot directive sets the directory for
 incoming IPP requests and HTML forms. If an absolute path is not
 provided then it is assumed to be relative to the 
#ServerRootServerRoot  directory. The default request directory is /var/spool/cups
.
Require 
Examples
Require group foo bar
Require user john mary
Require valid-user
Description
The Require directive specifies that authentication is
 required for the resource. The 
group keyword specifies
 that the authenticated user must be a member of one or more of the
 named groups that follow.
The user keyword specifies that the authenticated user
 must be one of the named users that follow.
The valid-user keyword specifies that any authenticated
 user may access the resource.
The default is to do no authentication. This directive must appear
 inside a 
#LocationLocation  directive.
RIPCache 
Examples
RIPCache 8m
RIPCache 1g
RIPCache 2048k
Description
The RIPCache directive sets the size of the memory cache
 used by Raster Image Processor ("RIP") filters such as 
imagetoraster
 and pstoraster. The size can be
 suffixed with a "k" for kilobytes, "m" for megabytes, or "g" for
 gigabytes. The default cache size is "8m", or 8 megabytes.
RootCertDuration 
Examples
RootCertDuration 300
RootCertDuration 0
Description
The RootCertDuration directive controls the interval
 between updates of the root authentication certificate. The default is 
300
 seconds which updates the root certificate approximately once
 every 5 minutes. Set the interval to 0 to disable certificate updates
 entirely.
RunAsUser 
Examples
RunAsUser Yes
RunAsUser No
Description
The RunAsUser directive controls whether the scheduler
 runs as the unpriviledged user account (usually 
lp). The
 default is 
No which leaves the scheduler running as the root
 user.
Note: Running as a non-priviledged user may prevent LPD and
 locally connected printers from working due to permission problems. The
 
lpd backend will automatically use a non-priviledged mode
 that is not 100% compliant with RFC 1179. The 
parallel, serial
, and usb backends will need write access to
 the corresponding device files.
Satisfy 
Examples
Satisfy all
Satisfy any
Description
The Satisfy directive specifies whether all conditions
 must be satisfied to allow access to the resource. If set to 
all, then all authentication and access control conditions must be satified
 to allow access.
Setting Satisfy to any allows a user to
 gain access if the authentication or access control requirements are
 satisfied. For example, you might require authentication for remote
 access, but allow local access without authentication.
The default is all. This directive must appear inside a #LocationLocation  directive.
ServerAdmin 
Examples
ServerAdmin user@host
ServerAdmin root@foo.bar.com
Description
The ServerAdmin directive identifies the email address
 for the administrator on the system. By default the administrator email
 address is 
root@server, where server is the
 server name.
ServerBin 
Examples
ServerBin /usr/lib/cups
ServerBin /foo/bar/lib/cups
Description
The ServerBin directive sets the directory for
 server-run executables. If an absolute path is not provided then it is
 assumed to be relative to the 
#ServerRootServerRoot  directory. The default executable directory is /usr/lib/cups.
ServerCertificate 
Examples
ServerCertificate /etc/cups/ssl/server.crt
Description
The ServerCertificate directive specifies the location
 of the SSL certificate file used by the server when negotiating
 encrypted connections. The certificate must not be encrypted (password
 protected) since the scheduler normally runs in the background and will
 be unable to ask for a password. The default certificate file is
 /etc/cups/ssl/server.crt
.
ServerKey 
Examples
ServerKey /etc/cups/ssl/server.key
Description
The ServerKey directive specifies the location of the
 SSL private key file used by the server when negotiating encrypted
 connections. The default key file is
 /etc/cups/ssl/server.crt.
ServerName
Examples
ServerName foo.domain.com
ServerName myserver.domain.com
Description
The ServerName directive specifies the hostname that is
 reported to clients. By default the server name is the hostname.
ServerRoot 
Examples
ServerRoot /etc/cups
ServerRoot /foo/bar/cups
Description
The ServerRoot directive specifies the absolute path to
 the server configuration and state files. It is also used to resolve
 relative paths in the
 cupsd.conf file. The default server
 directory is
 /etc/cups.
ServerTokens 
Examples
ServerTokens None
ServerTokens ProductOnly
ServerTokens Major
ServerTokens Minor
ServerTokens Minimal
ServerTokens OS
ServerTokens Full
Description
The ServerTokens directive specifies the information
 that is included in the Server header of HTTP responses. The default
 value is 
Minor which generates "CUPS/1.1".
SSLListen 
Examples
SSLListen 127.0.0.1:443
SSLListen 192.0.2.1:443
Description
The SSLListen directive specifies a network address and
 port to listen for secure connections. Multiple 
SSLListen directives can be provided to listen on multiple addresses.
The SSLListen directive is similar to the #SSLPortSSLPort  directive but allows you to restrict access to
 specific interfaces or networks.
SSLPort 
Examples
SSLPort 443
Description
The SSLPort directive specifies a port to listen on for
 secure connections. Multiple 
SSLPort lines can be
 specified to listen on multiple ports.
SystemGroup 
Examples
SystemGroup sys
SystemGroup system
SystemGroup root
Description
The SystemGroup directive specifies the system
 administration group for 
System authentication. More
 information can be found later in this chapter in 
#PRINTING_SECURITY"Printing System Security"
.
TempDir 
Examples
TempDir /var/tmp
TempDir /foo/bar/tmp
Description
The TempDir directive specifies an absolute path for the
 directory to use for temporary files. The default directory is
 /var/tmp
.
Temporary directories must be world-writable and should have the
 "sticky" permission bit enabled so that other users cannot delete
 filter temporary files. The following commands will create an
 appropriate temporary directory called
 /foo/bar/tmp:
mkdir /foo/bar/tmp ENTERchmod a+rwxt /foo/bar/tmp ENTER Timeout 
Examples
Timeout 300
Timeout 90
Description
The Timeout directive controls the amount of time to
 wait before an active HTTP or IPP request times out. The default
 timeout is 300 seconds.
User 
Examples
User lp
User guest
Description
The User directive specifies the UNIX user that filter
 and CGI programs run as. The default user is 
lp.
Changing the Client Configuration 
The CUPS client application (lp, lpr, and
 so forth) use the
 /etc/cups/client.conf file for default
 settings. The client application also look in the user's home directory
 for a file called
 .cupsrc. Each directive is listed on a
 line by itself followed by its value. Comments are introduced using the
 number sign ("#") character at the beginning of a line.
Since the client configuration file consists of plain text, you can
 use your favorite text editor to make changes to it.
Client Directives 
The client.conf file contains two directives that
 determine how the client behaves:
#EncryptionEncryption #ServerNameServerName Encryption 
Examples
Encryption Never
Encryption IfRequested
Encryption Required
Encryption Always
Description
The Encryption directive specifies the default
 encryption settings for the client. The default setting is
 IfRequested
.
ServerName 
Examples
ServerName foo.bar.com
ServerName 11.22.33.44
Description
The ServerName directive specifies sets the remote
 server that is to be used for all client operations. That is, it
 redirects all client requests to the remote server. The default is to
 use the local server ("
localhost").
Changing the Printer Configuration 
The CUPS scheduler (cupsd) uses the /etc/cups/printers.conf file to store the list of available printers. This file contains only
 locally defined printers, but not remote printers that are created
 automatically. Each directive is listed on a line by itself followed by
 its value. Comments are introduced using the number sign ("#")
 character at the beginning of a line.
Since the printer configuration file consists of plain text, you can
 use your favorite text editor to make changes to it.
Printer Directives 
The printers.conf file contains many directives that
 determine how the printer behaves:
#AcceptingAccepting #AllowUserAllowUser #DefaultPrinterDefaultPrinter #DenyUserDenyUser #DeviceURIDeviceURI     #InfoInfo #JobSheetsJobSheets #KLimitKLimit #PrinterLocationLocation #PageLimitPageLimit     #PrinterPrinter #QuotaPeriodQuotaPeriod #StateState #StateMessageStateMessage Accepting 
Examples
Accepting yes
Accepting no
Description
The Accepting directive defines the initial Boolean
 value for the
 printer-is-accepting-job attribute which can
 be set by the 
accept and reject commands.
This directive must appear inside a #PrinterPrinter  or #DefaultPrinterDefaultPrinter  directive.
AllowUser 
Examples
AllowUser foo_user
AllowUser bar_user
Description
The AllowUser directive adds a username to the requesting-user-name-allowed
 attribute which can be set by the lpadmin -u
 command.
This directive must appear inside a #PrinterPrinter  or #DefaultPrinterDefaultPrinter  directive.
DefaultPrinter 
Examples
<DefaultPrinter name/>
...
</Printer>
Description
The DefaultPrinter directive begins a printer definition
 for the default server destination. It can be added by the 
lpadmin
 command or if already defined, set as default by the lpoptions -d
 command.
DenyUser 
Examples
DenyUser foo_user
DenyUser bar_user
Description
The DenyUser directive adds a username to the requesting-user-name-allowed
 attribute which can be set by the lpadmin -u
 command.
This directive must appear inside a #PrinterPrinter  or #DefaultPrinterDefaultPrinter  directive.
DeviceURI 
Examples
DeviceURI socket://foo.bar.com:9100
Description
The DeviceURI directive defines the value of the device-uri-attribute
 attribute which can be set by the lpadmin -v
 command.
This directive must appear inside a #PrinterPrinter  or #DefaultPrinterDefaultPrinter  directive.
Info 
Examples
Info My Printer
Description
The Info directive defines the string for the printer-info
 attribute which can be set by the lpadmin -D command.
This directive must appear inside a #PrinterPrinter  or #DefaultPrinterDefaultPrinter  directive.
JobSheets 
Examples
JobSheets none,standard
Description
The JobSheets directive specifies the default banner
 pages to print before and after a print job. In the above example, only
 a
 standard banner will print after each job.
The lpoptions -o job-sheets= command can be used to set
 banners. For example, the following command would produce the same
 results of a
 standard banner at the end of each print job
 for the default printer.
 lpoptions -o job-sheets=none,standardIf only one banner file is specified, it will be printed before the
 files in the job. If a second banner file is specified, it is printed
 after the files in the job.
The available banner pages depend on the local system configuration;
 CUPS includes the following banner files:
none - Do not produce a banner page.classified - A banner page with a "classified" label at
 the top and bottom.
confidential - A banner page with a "confidential"
 label at the top and bottom.
secret - A banner page with a "secret" label at the top
 and bottom.
standard - A banner page with no label at the top and
 bottom.
topsecret - A banner page with a "top secret" label at
 the top and bottom.
unclassified - A banner page with an "unclassified"
 label at the top and bottom.
This directive must appear inside a #PrinterPrinter  or #DefaultPrinterDefaultPrinter  directive.
KLimit 
Examples
KLimit 1234
Description
The KLimit directive defines the value of the job-k-limit
 attribute which can be set by the lpadmin -o
 job-k-limit=
 command.
This directive must appear inside a #PrinterPrinter  or #DefaultPrinterDefaultPrinter  directive.
Location 
Examples
Location Building 3321
Description
The Location directive defines the string for the printer-location
 attribute which can be set by the lpadmin
 -L
 command.
 NOTE:Do not confuse this Location directive with the one in
 cupsd.conf. They are completely different.
This directive must appear inside a #PrinterPrinter  or #DefaultPrinterDefaultPrinter  directive.
PageLimit 
Examples
PageLimit 1234
Description
The PageLimit directive defines the value of the job-page-limit
 attribute which can be set by the lpadmin -o
 job-page-limit=
 command.
This directive must appear inside a #PrinterPrinter  or #DefaultPrinterDefaultPrinter  directive.
Printer 
Examples
<Printer name/>
...
</Printer>
Description
The Printer directive begins a printer definition. It
 can be added by the 
lpadmin command.
QuotaPeriod 
Examples
QuotaPeriod 604800
Description
The QuotaPeriod directive defines the value of the job-quota-period
 attribute which can be set by the lpadmin
 -o job-quota-period=
 command.
This directive must appear inside a #PrinterPrinter  or #DefaultPrinterDefaultPrinter  directive.
State 
Examples
State stopped
Description
The State directive defines the initial value of the printer-state
 attribute. The strings idle and stopped
 correspond to the IPP enumeration values.
This directive must appear inside a #PrinterPrinter  or #DefaultPrinterDefaultPrinter  directive.
StateMessage 
Examples
StateMessage Ready to print.
Description
The StateMessage directive defines the initial string
 for the
 printer-state-message attribute. The following are
 some example messages:
Connected to host_name...Connecting to printer_queue on port port_number...
Network host host_name is busy; will retry in 30
 seconds...
Printer busy; will retry in 10 seconds...Printer is busy; retrying print job...Print file accepted - job ID id_number.Ready to print.Waiting for job to completeThis directive must appear inside a #PrinterPrinter  or #DefaultPrinterDefaultPrinter  directive.
Changing the Classes Configuration 
The CUPS scheduler (cupsd) uses the /etc/cups/classes.conf file to store the list of available classes. This file contains only
 locally defined classes, but not remote or implicit classes that are
 created automatically. Each directive is listed on a line by itself
 followed by its value. Comments are introduced using the number sign
 ("#") character at the beginning of a line.
Since the classes configuration file consists of plain text, you can
 use your favorite text editor to make changes to it.
Classes Directives 
The classes.conf file contains many directives that
 determine how the classes behaves:
#ClassAcceptingAccepting #ClassAllowUserAllowUser #ClassClass #DefaultClassDefaultClass #ClassDenyUserDenyUser     #ClassInfoInfo #ClassJobSheetsJobSheets #ClassKLimitKLimit #ClassLocationLocation #ClassPageLimitPageLimit     #ClassPrinterPrinter #ClassQuotaPeriodQuotaPeriod #ClassStateState #ClassStateMessageStateMessage Accepting 
Examples
Accepting yes
Accepting no
Description
The Accepting directive defines the initial Boolean
 value for the
 printer-is-accepting-job attribute which can
 be set by the 
accept and reject commands.
This directive must appear inside a #ClassClass  or #DefaultClassDefaultClass  directive.
AllowUser 
Examples
AllowUser foo_user
AllowUser bar_user
Description
The AllowUser directive adds a username to the requesting-user-name-allowed
 attribute which can be set by the lpadmin -u
 command.
This directive must appear inside a #ClassClass  or #DefaultClassDefaultClass  directive.
Class 
Examples
<Class name/>
...
</Class>
Description
The Class directive begins a class definition. It can be
 added by the 
lpadmin -c command.
DefaultClass 
Examples
<DefaultClass name/>
...
</DefaultClass>
Description
The DefaultClass directive begins a class definition for
 the default server destination. It can be added by the 
lpadmin -c command or if already defined, set as default by the 
lpoptions -d command.
DenyUser 
Examples
DenyUser foo_user
DenyUser bar_user
Description
The DenyUser directive adds a username to the requesting-user-name-allowed
 attribute which can be set by the lpadmin -u
 command.
This directive must appear inside a #ClassClass  or #DefaultClassDefaultClass  directive.
Info 
Examples
Info My Printer
Description
The Info directive defines the string for the printer-info
 attribute which can be set by the lpadmin -D command.
This directive must appear inside a #ClassClass  or #DefaultClassDefaultClass  directive.
JobSheets 
Examples
JobSheets none,standard
Description
The JobSheets directive specifies the default banner
 pages to print before and after a print job. In the above example, only
 a
 standard banner will print after each job.
The lpoptions -o job-sheets= command can be used to set
 banners. For example, the following command would produce the same
 results of a
 standard banner at the end of each print job
 for the default class.
 lpoptions -o job-sheets=none,standardIf only one banner file is specified, it will be printed before the
 files in the job. If a second banner file is specified, it is printed
 after the files in the job.
The available banner pages depend on the local system configuration;
 CUPS includes the following banner files:
none - Do not produce a banner page.classified - A banner page with a "classified" label at
 the top and bottom.
confidential - A banner page with a "confidential"
 label at the top and bottom.
secret - A banner page with a "secret" label at the top
 and bottom.
standard - A banner page with no label at the top and
 bottom.
topsecret - A banner page with a "top secret" label at
 the top and bottom.
unclassified - A banner page with an "unclassified"
 label at the top and bottom.
This directive must appear inside a #ClassClass  or #DefaultClassDefaultClass  directive.
KLimit 
Examples
KLimit 1234
Description
The KLimit directive defines the value of the job-k-limit
 attribute which can be set by the lpadmin -o
 job-k-limit=
 command.
This directive must appear inside a #ClassClass  or #DefaultClassDefaultClass  directive.
Location 
Examples
Location Building 3321
Description
The Location directive defines the string for the printer-location
 attribute which can be set by the lpadmin
 -L
 command.
 NOTE:Do not confuse this Location directive with the one in
 cupsd.conf. They are completely different.
This directive must appear inside a #ClassClass  or #DefaultClassDefaultClass  directive.
PageLimit 
Examples
PageLimit 1234
Description
The PageLimit directive defines the value of the job-page-limit
 attribute which can be set by the lpadmin -o
 job-page-limit=
 command.
This directive must appear inside a #ClassClass  or #DefaultClassDefaultClass  directive.
Printer 
Examples
Printer foo
Printer bar
Printer foo@bar
Description
The Printer directive adds a printer to the class. It
 can be added by the 
lpadmin -c command.
 NOTE:Do not confuse this Printer directive with the one in
 printers.conf. They are completely different.
This directive must appear inside a #ClassClass  or #DefaultClassDefaultClass  directive.
QuotaPeriod 
Examples
QuotaPeriod 604800
Description
The QuotaPeriod directive defines the value of the job-quota-period
 attribute which can be set by the lpadmin
 -o job-quota-period=
 command.
This directive must appear inside a #ClassClass  or #DefaultClassDefaultClass  directive.
State 
Examples
State stopped
Description
The State directive defines the initial value of the printer-state
 attribute. The strings idle and stopped
 correspond to the IPP enumeration values.
This directive must appear inside a #ClassClass  or #DefaultClassDefaultClass  directive.
StateMessage 
Examples
StateMessage Ready to print.
Description
The StateMessage directive defines the initial string
 for the
 printer-state-message attribute. The following are
 some example messages:
Connected to host_name...Connecting to class_queue on port port_number...
Network host host_name is busy; will retry in 30
 seconds...
Printer busy; will retry in 10 seconds...Printer is busy; retrying print job...Print file accepted - job ID id_number.Ready to print.Waiting for job to completeThis directive must appear inside a #ClassClass  or #DefaultClassDefaultClass  directive.
Printing System Security 
CUPS provides support for address, certificate, and password (Basic
 and Digest) based authentication and access control. Certificate and
 password authentication provide ways to limit access to individual
 people or groups.
Address based access control allows you to limit access to specific
 systems, networks, or domains. While this does not provide
 authentication, it does allow you to limit the potential users of your
 system efficiently.
CUPS maintains a list of locations that have access control and/or
 authentication enabled. Locations are specified using the 
#LocationLocation  directive:
<Location /resource>
#AuthClassAuthClass  ...
#AuthGroupNameAuthGroupName  ...
#AuthTypeAuthType  ...
#OrderOrder  ...
#AllowAllow  from ...
#DenyDeny  from ...
</Location>
Locations generally follow the directory structure of the #DocumentRootDocumentRoot  directory, however CUPS does have several
 virtual locations for administration, classes, jobs, and printers:
LocationDescription /admin The path for all administration operations. /classes The path for all classes. /classes/name The resource for class name. /jobs The path for all jobs. /jobs/id The resource for job id. /printers The path for all printers. /printers/name The path for printer name. /printers/name.ppd The PPD file path for printer name
. 
Authentication Using Certificates 
CUPS supports a local certificate-based authentication scheme that
 can be used in place of 
Basic or Digest authentication by clients connecting through the 
localhost interface. Certificate authentication is not supported or allowed from
 clients on any other interface.
Certificates are 128-bit random numbers that refer to an internal
 authentication record in the server. A client connecting via the 
localhost
 interface sends a request with an authorization header
 of:
Authorization: Local 0123456789ABCDEF0123456789ABCDEF
The server then looks up the local certificate and authenticates
 using the username associated with it.
Certificates are generated by the server automatically and stored in
 the
 /etc/cups/certs directory using the process ID of the
 CGI program started by the server. Certificate files are only readable
 by the 
#UserUser  and #GroupGroup
 defined in the cupsd.conf file. When the CGI
 program ends the certificate is removed and invalidated automatically.
The special file /etc/cups/certs/0 defines the root
 certificate
 which can be used by any client running as the
 super-user or another user that is part of the group defined by the 
#SystemGroupSystemGroup  directive. The root certificate is
 automatically regenerated every 5 minutes.
Using Basic Authentication 
Basic authentication uses UNIX users and passwords to authenticate
 access to resources such as printers and classes, and to limit access
 to administrative functions.
 NOTE:Basic authentication sends the username and password Base64 encoded
 from the client to the server, so it offers no protection against
 eavesdropping. This means that a malicious user can monitor network
 packets and discover valid users and passwords that could result in a
 serious compromise in network security. Use Basic authentication with
 extreme care.
The CUPS implementation of Basic authentication does not allow access
 through user accounts without a password. If you try to authenticate
 using an account without a password, your access will be immediately
 blocked.
Once a valid username and password is authenticated by CUPS, any
 additional group membership requirements are checked.
 NOTE:The root user is considered by CUPS to be a member of every group.
Use the AuthType directive to enable Basic
 authentication:
AuthType Basic
Using Digest Authentication 
Digest authentication uses users and passwords defined in the /etc/cups/passwd.md5
 file to authenticate access to resources
 such as printers and classes, and to limit access to administrative
 functions.
 NOTE:Unlike Basic authentication, Digest passes the MD5 sum (basically a
 complicated checksum) of the username and password instead of the
 strings themselves. Also, Digest authentication does not use the UNIX
 password file, so if an attacker does discover the original password it
 is less likely to result in a serious security problem so long as you
 use a different UNIX password than the corresponding Digest password.
The current CUPS implementation of Digest authentication uses the
 client's hostname or IP address for the "nonce" value. The nonce value
 is an additional string added to the username and password to make
 guessing the password more difficult. The server checks that the nonce
 value matches the client's hostname or address and rejects the MD5 sum
 if it doesn't. Future versions of CUPS will support Digest "session"
 authentication which adds the request data to the MD5 sum, providing
 even better authentication and security.
Digest authentication does not guarantee that an attacker cannot gain
 unauthorized access, but it is safer than Basic authentication and
 should be used in place of Basic authentication whenever possible.
 Support for Digest authentication in web browsers is not yet
 universally available.
The lppasswd(1) command is used to add, change, or
 remove accounts from the
 passwd.md5 file. To add a user to
 the default system group, type:
lppasswd -a user ENTERPassword: 
(password) ENTER [password is not echoed]
Password again: 
(password) ENTER [password is not echoed]
Once added, a user can change his/her password by typing:
lppasswd ENTEROld password: 
(password) ENTER [password is not echoed]
Password: 
(password) ENTER [password is not echoed]
Password again: 
(password) ENTER [password is not echoed]
To remove a user from the password file, type:
lppasswd -x user ENTEROnce a valid username and password is authenticated by CUPS, any
 additional group membership requirements are checked.
 NOTE:The root user is considered by CUPS to be a member of every group.
Use the AuthType directive to enable Digest
 authentication:
AuthType Digest
System and Group Authentication 
The #AuthClassAuthClass  directive
 controls the level of authentication to perform. 
System and 
Group authentication extend the normal user-based
 authentication to require membership in a UNIX group. For 
System authentication each user must belong to the 
sys, system
, or root group; the actual group depends on
 the operating system.
For Group authentication each user must belong to the
 group named by the 
#AuthGroupNameAuthGroupName  directive:
<Location /path>
AuthType Digest
AuthClass Group
AuthGroupName mygroup
</Location>
The named group must be a valid UNIX user group, usually defined in
 the
 /etc/group or /etc/netgroup files.
 Additionally, when using Digest authentication you need to create user
 accounts with the named group:
lppasswd -g mygroup -a user ENTERPassword: 
(password) ENTER [password is not echoed]
Password again: 
(password) ENTER [password is not echoed]
Printer Accounting 
CUPS maintains a log of all accesses, errors, and pages that are
 printed. The log files are normally stored in the
 /var/log/cups directory. You can change this by editing the
 /etc/cups/cupsd.conf configuration file.
The access_log File 
The access_log file lists each HTTP resource that is
 accessed by a web browser or CUPS/IPP client. Each line is in the
 so-called "Common Log Format" used by many web servers and web
 reporting tools:
host group user date-time \"method resource version\" status bytes
127.0.0.1 - - [20/May/1999:19:20:29 +0000] "POST /admin/ HTTP/1.1" 401 0
127.0.0.1 - mike [20/May/1999:19:20:31 +0000] "POST /admin/ HTTP/1.1" 200 0
The host field will normally only be an IP address unless you
 have enabled the 
#HostNameLookupsHostNameLookups  directive in the cupsd.conf file.
The group field always contains "-" in CUPS.
The user field is the authenticated username of the requesting
 user. If no username and password is supplied for the request then this
 field contains "-".
The date-time field is the date and time of the request in
 local time and is in the format:
[DD/MON/YYYY:HH:MM:SS +ZZZZ]
where ZZZZ is the timezone offset in hours and minutes from
 coordinated universal time (UTC). UTC may sometimes be referred to as
 GMT or ZULU on legacy systems.
The method field is the HTTP method used ("GET", "PUT",
 "POST", etc.)
The resource field is the filename of the requested resource.
The version field is the HTTP specification version used by
 the client. For CUPS clients this will always be "HTTP/1.1".
The status field contains the HTTP result status of the
 request. Usually it is "200", but other HTTP status codes are possible.
 For example, 401 is the "unauthorized access" status in the example
 above.
The bytes field contains the number of bytes in the request.
 For POST requests the
 bytes field contains the number of bytes
 that was received from the client.
The error_log File 
The error_log file lists messages from the scheduler
 (errors, warnings, etc.):
level date-time message
I [20/May/1999:19:18:28 +0000] Job 1 queued on 'DeskJet' by 'mike'.
I [20/May/1999:19:21:02 +0000] Job 2 queued on 'DeskJet' by 'mike'.
I [20/May/1999:19:22:24 +0000] Job 2 was cancelled by 'mike'.
The level field contains the type of message:
E - An error occurred.W - The server was unable to perform some action.I - Informational message.D - Debugging message.The date-time field contains the date and time of when the
 page started printing. The format of this field is identical to the
 data-time
 field in the access_log file.
The message fields contains a free-form textual message.
The page_log File 
The page_log file lists each page that is sent to a
 printer. Each line contains the following information:
printer user job-id date-time page-number num-copies job-billing hostname
DeskJet root 2 [20/May/1999:19:21:05 +0000] 1 0 acme-123 localhost
The printer field contains the name of the printer that
 printed the page. If you send a job to a printer class, this field will
 contain the name of the printer that was assigned the job.
The user field contains the name of the user (the IPP requesting-user-name
 attribute) that submitted this file for
 printing.
The job-id field contains the job number of the page being
 printed. Job numbers are reset to 1 whenever the CUPS server is
 started, so don't depend on this number being unique!
The date-time field contains the date and time of when the
 page started printing. The format of this field is identical to the
 data-time
 field in the access_log file.
The page-number and num-pages fields contain the page
 number and number of copies being printed of that page. For printer
 that can not produce copies on their own, the
 num-pages field
 will always be 1.
The job-billing field contains a copy of the job-billing attribute provided with the IPP 
create-job or print-job
 requests or "-" if none was provided.
The hostname field contains the name of the host (the IPP job-originating-host-name
 attribute) that originated the print
 job.
File Typing and Filtering 
CUPS provides a MIME-based file typing and filtering mechanism to
 convert files to a printable format for each printer. On startup the
 CUPS server reads MIME database files from the
 /etc/cups directory (or a directory specified by the 
#ServerRootServerRoot
 directive) to build a file type and conversion
 database in memory. These database files are plain ASCII text and can
 be edited with your favorite text editor.
The mime.types and mime.convs files define the
 standard file types and filters that are available on the system.
mime.types 
The mime.types file defines the known file types. Each
 line of the file starts with the MIME type and may be followed by one
 or more file type recognition rules. For example, the 
text/html file type is defined as:
text/html       html htm \
	printable(0,1024) + \
	(string(0,"<HTML>") string(0,"<!DOCTYPE"))
The first two rules say that any file with an extension of .html or
 .htm is a HTML file. The third rule says that any file
 whose first 1024 characters are printable text and starts with the
 strings 
<HTML> or <!DOCTYPE is a HTML file as
 well.
The first two rules deal solely with the name of the file being
 typed. This is useful when the original filename is known, however for
 print files the server doesn't have a filename to work with. The third
 rule takes care of this possibility and automatically figures out the
 file type based upon the contents of the file instead.
The available tests are:
( expr ) - Parenthesis for expression grouping+ - Logical AND, or whitespace - Logical OR! - Logical NOTmatch("pattern") - Pattern match on filenameextension - Pattern match on "*.extension"ascii(offset,length) - True if bytes are valid
 printable ASCII (CR, NL, TAB, BS, 32-126)
printable(offset,length) - True if bytes are printable
 8-bit chars (CR, NL, TAB, BS, 32-126, 160-254)
string(offset,"string") - True if bytes are identical
 to string
istring(offset,"string") - True if bytes are identical
 to string after reducing both strings to lowercase
contains(offset,range,"string") - True if the range of
 bytes contains the string
char(offset,value) - True if byte is identicalshort(offset,value) - True if 16-bit integer is
 identical (network or "big-endian" byte order)
int(offset,value) - True if 32-bit integer is identical
 (network or "big-endian" byte order)
locale("string") - True if current locale matches
 string
All numeric values can be in decimal (123), octal (0123), or
 hexadecimal (0x123) as desired.
Strings can be in quotes, all by themselves, as a string of
 hexadecimal values, or some combination:
"string"
'string'
string
<737472696e67>
<7374>ring
As shown in the text/html example, rules can continue on
 multiple lines using the backslash (\) character. A more complex
 example is the 
image/jpeg rules:
image/jpeg      jpeg jpg jpe string(0,<FFD8FF>) &&\
	(char(3,0xe0) char(3,0xe1) char(3,0xe2) char(3,0xe3)\
	 char(3,0xe4) char(3,0xe5) char(3,0xe6) char(3,0xe7)\
	 char(3,0xe8) char(3,0xe9) char(3,0xea) char(3,0xeb)\
	 char(3,0xec) char(3,0xed) char(3,0xee) char(3,0xef))
This rule states that any file with an extension of .jpeg, .jpg
, or .jpe is a JPEG file. In addition, any file
 starting with the hexadecimal string 
<FFD8FF> (JPEG
 Start-Of-Image) followed by a character between and including 
0xe0
 and 0xef (JPEG APPn markers) is also a JPEG
 file.
mime.convs 
The mime.convs file defines all of the filter programs
 that are known to the system. Each line consists of:
source destination cost program
text/plain application/postscript 50 texttops
application/vnd.cups-postscript application/vnd.cups-raster 50 pstoraster
image/* application/vnd.cups-postscript 50 imagetops
image/* application/vnd.cups-raster 50 imagetoraster
The source field is a MIME type, optionally using a wildcard
 for the super-type or sub-type (e.g. "text/plain", "image/*",
 "*/postscript").
The destination field is a MIME type defined in the mime.types
 file.
The cost field defines a relative cost for the filtering
 operation from 1 to 100. The cost is used to choose between two
 different sets of filters when converting a file. For example, to
 convert from 
image/jpeg to application/vnd.cups-raster
, you could use the imagetops and 
pstoraster filters for a total cost of 100, or the imagetoraster
 filter for a total cost of 50.
The program field defines the filter program to run; the
 special program "-" can be used to make two file types equivalent. The
 program must accept the standard filter arguments and environment
 variables described in the CUPS Interface Design Description and CUPS
 Software Programmers Manual:
program job user title options [filename]
If specified, the filename argument defines a file to read
 when filtering, otherwise the filter must read from the standard input.
 All filtered output must go to the standard output.
Adding Filetypes and Filters 
Adding a new file type or filter is fairly straight-forward. Rather
 than adding the new type and filter to the
 mime.types and mime.convs
 files which are overwritten when you upgrade to a new
 version of CUPS, you simple need to create new files with
 .types and
 .convs extensions in the /etc/cups directory.
 We recommend that you use the product or format name, e.g.:
myproduct.types
myproduct.convs
If you are providing a filter for a common file format or printer,
 add the company or author name:
acme-msword.types
acme-msword.convs
This will help to prevent name collisions if you install many
 different file types and filters.
Once you choose the names for these files, create them using your
 favorite text editor as described earlier in this chapter. Once you
 have created the files, restart the 
cupsd process as
 described earlier in 
#RESTARTING"Restarting the CUPS Server" .
Printer Drivers and PPD Files 
Most CUPS printer drivers utilize one or more printer-specific
 filters and a PPD file for each printer model. Printer driver filters
 are registered via the PPD file using 
cupsFilter attributes:
*cupsFilter: "application/vnd.cups-raster 0 rastertohp"
The filter is specified using the source file type only; the
 destination file type is assumed to be 
printer/name -
 suitable for sending to the printer.
Writing Your Own Filter or Printer Driver 
CUPS supports an unlimited number of file formats and filters, and
 can handle any printer. If you'd like to write a filter or printer
 driver for your favorite file format or printer, consult the CUPS
 Software Programmers Manual for step-by-step instructions.
7 - Printing with Other
 Systems
This chapter describes how to print from client systems that use the
 LPD, Mac OS, or Windows printing protocols.
The Basics 
CUPS is based on the IPP protocol, so any system that supports IPP
 can send jobs to and receive jobs from CUPS automatically. However, not
 all systems support IPP yet. This chapter will show you how to connect
 these systems to your CUPS server, either to accept jobs from your
 server for printing, or to send jobs to your server.
Printing from LPD Clients 
CUPS supports limited functionality for LPD-based clients. With LPD
 you can print files to specific printers, list the queue status, and so
 forth. However, the automatic client configuration and printer options
 are not supported by the LPD protocol, so you must manually configure
 each client for the printers it needs to access.
The cups-lpd(8) program provides support for LPD clients
 and can be used from either the 
inetd(8) or xinetd(8)
 programs. Add the following line to the /etc/inetd.conf
 file to enable LPD support on your server through
 the 
inetd program:
printer stream tcp nowait lp /usr/lib/cups/daemon/cups-lpd cups-lpd
The path to the cups-lpd may vary depending on your
 installation.
Once you have added this line, send the inetd process a HUP
 signal or reboot the system:
killall -HUP inetd ENTER [IRIX and some versions of Linux]
kill -HUP pid ENTER [Others]reboot ENTER [For all systems if the HUP signal fails]If you are using the xinetd program, create a file named /etc/xinetd.d/printer
 containing the following lines:
service printer
{
socket_type = stream
protocol = tcp
wait = no
user = lp
server = /usr/lib/cups/daemon/cups-lpd
}
The xinetd program automatically reads the new
 configuration file and enables LPD printing support.
Warning:cups-lpd currently does not perform any access control
 based on the settings in
 cupsd.conf or in the hosts.allow
 or hosts.deny files used by TCP wrappers.
 Therefore, running 
cups-lpd on your server will allow any
 computer on your network (and perhaps the entire Internet) to print to
 your server.
While xinetd has built-in access control support, you
 should use the TCP wrappers package with 
inetd to limit
 access to only those computers that should be able to print through
 your server.
Printing to LPD Servers 
CUPS provides the lpd backend for printing to LPD-based
 servers and printers. Use a device URI of 
lpd://server/name to print to a printer on an LPD server, where 
server is
 the hostname or IP address of the server and 
name is the
 queue name. Additional options can be specified after the remote queue
 name to control how the LPD requests are sent - consult 
#COMMON_NETWORKAppendix B - Common Network Settings
 for a complete description.
Microsoft Windows NT provides an LPD service under the name "TCP/IP
 Printing Services". To enable LPD printing on NT, open the "Services"
 control panel, select the "TCP/IP Printing Services" service, and click
 on the "Start" button. Any shared printer will then be available via
 the LPD protocol.
Printing from Mac OS 10.2 and Later Clients 
Since Mac OS 10.2 uses CUPS as its printing system, all CUPS printers
 will be available to the clients automatically.
Note:Certain legacy MacOS X applications, including most Adobe
 applications, produce PICT files with embedded PostScript. Since the
 filter needed to convert these files to pure PostScript is only
 available on MacOS X, you need to either use a MacOS X print server or
 replace the MacOS X IPP backend with the standard CUPS IPP backend. The
 CUPS IPP backend will detect and locally convert these print files to
 PostScript prior to sending the job to the server.
Printing from Mac OS 10.1 and Earlier Clients 
CUPS does not provide support for Mac OS 10.1 and earlier directly.
 However, there are several free and commercial software packages that
 do.
Columbia Appletalk Package (CAP) 
Because the CAP LaserWriter server (lwsrv(8)) does not
 support specification of PPD files, we do not recommend that you use
 CAP with CUPS. However, you can run the 
lpsrv program for
 limited printing with the command:
lwsrv -n "
Name" -p printer -a /usr/lib/adicts -f /usr/lib/LW+Fonts
where Name is the name you want to use when sharing the
 printer, and 
printer is the name of the CUPS print queue.
XINET KA/Spool 
To use your system as a print server for Mac OS clients, configure
 each printer using a 
papserver(8) in the /usr/adm/appletalk/services
 file, specifying the corresponding
 PPD file in the
 /etc/cups/ppd directory for each printer.
 For a printer named 
MyPrinter the entry would look like:
/usr/etc/appletalk/papserver -I -L -P /etc/cups/ppd/MyPrinter.ppd \
"Printer Description" MyPrinter
 NOTE:Enter the text above on a single line without the backslash (\)
 character.
Netatalk 
To use your system as a print server for Mac OS clients, configure
 each printer in the
 papd.conf file, specifying the
 corresponding PPD file in the
 /etc/cups/ppd directory for
 each printer. For a printer named 
MyPrinter the entry
 would look like:
Printer Name@Zone Name:\
:pr=|/usr/bin/lp -d MyPrinter:\
:op=daemon:\
:pd=/etc/cups/ppd/MyPrinter.ppd:
Printing to Mac OS 10.2 and Later Servers 
Since MacOS 10.2 and later use CUPS, all you need to do is enable
 printer sharing to allow CUPS clients to print to a Mac OS server. You
 will need to download and install ESP Ghostscript on your server to
 provide PostScript printing support for non-PostScript printers,
 however.
Printing to Mac OS 10.1 and Earlier Servers 
CUPS currently does not provide a backend to communicate with a Mac
 OS 10.1 and earlier server. However, you can write and install a short
 shell script in the
 /usr/lib/cups/backend directory that
 sends a print file using the appropriate command. The following is a
 short script that will run the 
papif command provided with
 CAP.
After copying this script to /usr/lib/cups/backend/cap,
 specify a device URI of 
cap://server/printer to use this
 backend with a print queue.
"/usr/lib/cups/backend/cap"#!/bin/sh
#
# Usage: cap job user title copies options [filename]
#
# No arguments means show available devices...
if test ${#argv} = 0; then
echo "network cap \"Unknown\" \"Mac OS Printer via CAP\""
exit 0
fi
# Collect arguments...
user=$2
copies=$4
if test ${#argv} = 5; then
# Get print file from stdin; copies have already been handled...
file=/var/tmp/$$.prn
copies=1
cat > $file
else
# Print file is on command-line...
file=$6
fi
# Create a dummy cap.printers file for this printer based
# upon a device URI of "cap://server/printer"...
echo $PRINTER/$DEVICE_URI | \
awk -F/ '{print $1 "=" $5 ":LaserWriter@" $4}' > /var/tmp/$$.cap
CAPPRINTERS=/var/tmp/$$.cap; export CAPPRINTERS
# Send the file to the printer, once for each copy. This assumes that you
# have properly initialized the cap.printers file...
while [ $copies -gt 0 ]; do
papif -n $user < $file
copies=`expr $copies - 1`
done
# Remove any temporary files...
if test ${#argv} = 5; then
/bin/rm -f $file
fi
/bin/rm -f /var/tmp/$$.cap
exit 0
Printing from Windows Clients 
While CUPS does not provide Windows support directly, the free SAMBA
 software package does. SAMBA version 2.0.6 is the first release of
 SAMBA that supports CUPS. You can download SAMBA from:
http://www.samba.orghttp://www.samba.org To configure SAMBA for CUPS, edit the smb.conf file and
 replace the existing printing commands and options with the line:
printing = cups
printcap name = cups
That's all there is to it! Remote users will now be able to browse
 and print to printers on your system.
Exporting Printer Drivers 
You can optionally export printer drivers from your CUPS server using
 the 
cupsaddsmb command and the SAMBA 2.2.0 or higher
 software.
Before you can export the printers you must download the CUPS drivers
 for Windows from the CUPS site (
http://www.cups.org/http://www.cups.org/
) or the current Adobe PostScript printer
 drivers from the Adobe web site (
http://www.adobe.com/http://www.adobe.com/
). If you download the Adobe drivers, use the
 free 
unzip software to extract the files from the
 self-extracting ZIP file containing the drivers; you will need the
 following files:
ADFONTS.MFM
ADOBEPS4.DRV
ADOBEPS4.HLP
ADOBEPS5.DLL
ADOBEPSU.DLL
ADOBEPSU.HLP
DEFPRTR2.PPD
ICONLIB.DLL
PSMON.DLL
Copy these files to the /usr/share/cups/drivers directory
 - you may need to rename some of the files so the filenames are all
 UPPERCASE.
Next, configure SAMBA (via the smb.conf file) to support
 printing through CUPS and provide a printer driver download share, as
 follows:
[global]
load printers = yes
printing = cups
printcap name = cups
[printers]
comment = All Printers
path = /var/spool/samba
browseable = no
public = yes
guest ok = yes
writable = no
printable = yes
printer admin = root
[print$]
comment = Printer Drivers
path = /etc/samba/drivers
browseable = yes
guest ok = no
read only = yes
write list = root
This configuration assumes a FHS-compliant installation of SAMBA;
 adjust the [printers] and [print$] share paths accordingly on your
 system as needed. That is, the directory for your printer drivers can
 be anywhere on the system; just make sure it is writable by the users
 specified by the 
write list directive plus readable and
 executable by all users. Also, make sure that you have SAMBA passwords
 defined for each user in the 
write list using SAMBA's smbpasswd(1)
 command. Otherwise you will not be able to
 authenticate.
Finally, run the cupsaddsmb command to export the
 printer drivers for one or more queues:
cupsaddsmb -U root printer1 ... printerN ENTERRunning cupsaddsmb with the -a option will
 export all printers:
cupsaddsmb -U root -a ENTERNotice in the above examples that the user root was used
 which was defined in the 
write list of the smb.conf file.
Printing to Windows Servers 
CUPS can print to Windows servers in one of two ways. The first way
 uses the LPD protocol on the CUPS system and the "TCP/IP Printing
 Services" on the Windows system. You can find out more about this
 configuration in the 
#LPDLPD  section earlier in this
 chapter.
The second way is through the Microsoft Server Message Block ("SMB")
 protocol. Support for this protocol is provided with the free SAMBA
 software package. You can download SAMBA from:
http://www.samba.orghttp://www.samba.org To configure CUPS for SAMBA, run the following command:
ln -s `which smbspool` /usr/lib/cups/backend/smb ENTERThe smbspool(1) program is provided with SAMBA starting
 with SAMBA 2.0.6. Once you have made the link you can configure your
 printers with one of the following device URIs:
smb://workgroup/server/sharename
smb://server/sharename
smb://user:pass@workgroup/server/sharename
smb://user:pass@server/sharename
The workgroup name need only be specified if your system
 is using a different workgroup. The 
user:pass strings are
 required when printing to Windows NT servers or to shares with
 passwords enabled under Windows 95 and 98.
A - Software License Agreement 
Common UNIX Printing System License
 Agreement
Copyright 1997-2005 by Easy Software Products
 44141 AIRPORT VIEW DR STE 204
 HOLLYWOOD, MARYLAND 20636 USA
 Voice: +1.301.373.9600
 Email: mailto:cups-info@cups.orgcups-info@cups.org  WWW: http://www.cups.orghttp://www.cups.org 
Introduction 
The Common UNIX Printing SystemTM, ("CUPSTM"),
 is provided under the GNU General Public License ("GPL") and GNU
 Library General Public License ("LGPL"), Version 2, with exceptions for
 Apple operating systems and the OpenSSL toolkit. A copy of the
 exceptions and licenses follow this introduction.
The GNU LGPL applies to the CUPS API library, located in the "cups"
 subdirectory of the CUPS source distribution and in the "cups" include
 directory and library files in the binary distributions. The GNU GPL
 applies to the remainder of the CUPS distribution, including the
 "pdftops" filter which is based upon Xpdf and the CUPS imaging library.
For those not familiar with the GNU GPL, the license basically allows
 you to:
Use the CUPS software at no charge.Distribute verbatim copies of the software in source or binary form.Sell verbatim copies of the software for a media fee, or sell
 support for the software.
Distribute or sell printer drivers and filters that use CUPS so long
 as source code is made available under the GPL.
What this license does not allow you to do is make changes or
 add features to CUPS and then sell a binary distribution without source
 code. You must provide source for any new drivers, changes, or
 additions to the software, and all code must be provided under the GPL
 or LGPL as appropriate. The only exceptions to this are the portions of
 the CUPS software covered by the Apple operating system license
 exceptions outlined later in this license agreement.
The GNU LGPL relaxes the "link-to" restriction, allowing you to
 develop applications that use the CUPS API library under other licenses
 and/or conditions as appropriate for your application.
License Exceptions 
In addition, as the copyright holder of CUPS, Easy Software Products
 grants the following special exceptions:
Apple Operating System Development License Exception;
Software that is developed by any person or entity for an Apple
 Operating System ("Apple OS-Developed Software"), including but not
 limited to Apple and third party printer drivers, filters, and backends
 for an Apple Operating System, that is linked to the CUPS imaging
 library or based on any sample filters or backends provided with CUPS
 shall not be considered to be a derivative work or collective work
 based on the CUPS program and is exempt from the mandatory source code
 release clauses of the GNU GPL. You may therefore distribute linked
 combinations of the CUPS imaging library with Apple OS-Developed
 Software without releasing the source code of the Apple OS-Developed
 Software. You may also use sample filters and backends provided with
 CUPS to develop Apple OS-Developed Software without releasing the
 source code of the Apple OS-Developed Software.
An Apple Operating System means any operating system software
 developed and/or marketed by Apple Computer, Inc., including but not
 limited to all existing releases and versions of Apple's Darwin, Mac OS
 X, and Mac OS X Server products and all follow-on releases and future
 versions thereof.
This exception is only available for Apple OS-Developed Software and
 does not apply to software that is distributed for use on other
 operating systems.
All CUPS software that falls under this license exception have the
 following text at the top of each source file:
This file is
 subject to the Apple OS-Developed Software exception.
OpenSSL Toolkit License Exception;
Easy Software Products explicitly allows the compilation and
 distribution of the CUPS software with the OpenSSL Toolkit.
No developer is required to provide these exceptions in a derived
 work.
Trademarks 
Easy Software Products has trademarked the Common UNIX Printing
 System, CUPS, and CUPS logo. You may use these names and logos in any
 direct port or binary distribution of CUPS. Please contact Easy
 Software Products for written permission to use them in derivative
 products. Our intention is to protect the value of these trademarks and
 ensure that any derivative product meets the same high-quality
 standards as the original.
Binary Distribution Rights 
Easy Software Products also sells rights to the CUPS source code
 under a binary distribution license for vendors that are unable to
 release source code for their drivers, additions, and modifications to
 CUPS under the GNU GPL and LGPL. For information please contact us at
 the address shown above.
The Common UNIX Printing System provides a "pdftops" filter that is
 based on the Xpdf software. For binary distribution licensing of this
 software, please contact:
 Derek B. Noonburg
 Email: mailto:derekn@foolabs.comderekn@foolabs.com  WWW: http://www.foolabs.com/xpdf/http://www.foolabs.com/xpdf/
Support 
Easy Software Products sells software support for CUPS as well as a
 commercial printing product based on CUPS called ESP Print Pro. You can
 find out more at our web site:
http://www.easysw.com/http://www.easysw.com/ GNU GENERAL PUBLIC LICENSE 
Version 2, June 1991
Copyright 1989, 1991 Free Software Foundation, Inc.
59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Everyone is permitted to copy and distribute verbatim
copies of this license document, but changing it is not allowed.
Preamble 
The licenses for most software are designed to take away your freedom
 to share and change it. By contrast, the GNU General Public License is
 intended to guarantee your freedom to share and change free
 software--to make sure the software is free for all its users. This
 General Public License applies to most of the Free Software
 Foundation's software and to any other program whose authors commit to
 using it. (Some other Free Software Foundation software is covered by
 the GNU Library General Public License instead.) You can apply it to
 your programs, too.
When we speak of free software, we are referring to freedom, not
 price. Our General Public Licenses are designed to make sure that you
 have the freedom to distribute copies of free software (and charge for
 this service if you wish), that you receive source code or can get it
 if you want it, that you can change the software or use pieces of it in
 new free programs; and that you know you can do these things.
To protect your rights, we need to make restrictions that forbid
 anyone to deny you these rights or to ask you to surrender the rights.
 These restrictions translate to certain responsibilities for you if you
 distribute copies of the software, or if you modify it.
For example, if you distribute copies of such a program, whether
 gratis or for a fee, you must give the recipients all the rights that
 you have. You must make sure that they, too, receive or can get the
 source code. And you must show them these terms so they know their
 rights.
We protect your rights with two steps: (1) copyright the software,
 and (2) offer you this license which gives you legal permission to
 copy, distribute and/or modify the software.
Also, for each author's protection and ours, we want to make certain
 that everyone understands that there is no warranty for this free
 software. If the software is modified by someone else and passed on, we
 want its recipients to know that what they have is not the original, so
 that any problems introduced by others will not reflect on the original
 authors' reputations.
Finally, any free program is threatened constantly by software
 patents. We wish to avoid the danger that redistributors of a free
 program will individually obtain patent licenses, in effect making the
 program proprietary. To prevent this, we have made it clear that any
 patent must be licensed for everyone's free use or not licensed at all.
The precise terms and conditions for copying, distribution and
 modification follow.
GNU GENERAL PUBLIC LICENSE
 TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
This License applies to any program or other work which contains a
 notice placed by the copyright holder saying it may be distributed
 under the terms of this General Public License. The "Program", below,
 refers to any such program or work, and a "work based on the Program"
 means either the Program or any derivative work under copyright law:
 that is to say, a work containing the Program or a portion of it,
 either verbatim or with modifications and/or translated into another
 language. (Hereinafter, translation is included without limitation in
 the term "modification".) Each licensee is addressed as "you".
Activities other than copying, distribution and modification are not
 covered by this License; they are outside its scope. The act of running
 the Program is not restricted, and the output from the Program is
 covered only if its contents constitute a work based on the Program
 (independent of having been made by running the Program). Whether that
 is true depends on what the Program does.
You may copy and distribute verbatim copies of the Program's source
 code as you receive it, in any medium, provided that you conspicuously
 and appropriately publish on each copy an appropriate copyright notice
 and disclaimer of warranty; keep intact all the notices that refer to
 this License and to the absence of any warranty; and give any other
 recipients of the Program a copy of this License along with the
 Program.
You may charge a fee for the physical act of transferring a copy, and
 you may at your option offer warranty protection in exchange for a fee.
You may modify your copy or copies of the Program or any portion of
 it, thus forming a work based on the Program, and copy and distribute
 such modifications or work under the terms of Section 1 above, provided
 that you also meet all of these conditions:
You must cause the modified files to carry prominent notices stating
 that you changed the files and the date of any change.
You must cause any work that you distribute or publish, that in
 whole or in part contains or is derived from the Program or any part
 thereof, to be licensed as a whole at no charge to all third parties
 under the terms of this License.
if the modified program normally reads commands interactively when
 run, you must cause it, when started running for such interactive use
 in the most ordinary way, to print or display an announcement including
 an appropriate copyright notice and a notice that there is no warranty
 (or else, saying that you provide a warranty) and that users may
 redistribute the program under these conditions, and telling the user
 how to view a copy of this License. (Exception: if the Program itself
 is interactive but does not normally print such an announcement, your
 work based on the Program is not required to print an announcement.)
These requirements apply to the modified work as a whole. If
 identifiable sections of that work are not derived from the Program,
 and can be reasonably considered independent and separate works in
 themselves, then this License, and its terms, do not apply to those
 sections when you distribute them as separate works. But when you
 distribute the same sections as part of a whole which is a work based
 on the Program, the distribution of the whole must be on the terms of
 this License, whose permissions for other licensees extend to the
 entire whole, and thus to each and every part regardless of who wrote
 it.
Thus, it is not the intent of this section to claim rights or contest
 your rights to work written entirely by you; rather, the intent is to
 exercise the right to control the distribution of derivative or
 collective works based on the Program.
In addition, mere aggregation of another work not based on the
 Program with the Program (or with a work based on the Program) on a
 volume of a storage or distribution medium does not bring the other
 work under the scope of this License.
You may copy and distribute the Program (or a work based on it,
 under Section 2) in object code or executable form under the terms of
 Sections 1 and 2 above provided that you also do one of the following:
Accompany it with the complete corresponding machine-readable source
 code, which must be distributed under the terms of Sections 1 and 2
 above on a medium customarily used for software interchange; or,
Accompany it with a written offer, valid for at least three years,
 to give any third party, for a charge no more than your cost of
 physically performing source distribution, a complete machine-readable
 copy of the corresponding source code, to be distributed under the
 terms of Sections 1 and 2 above on a medium customarily used for
 software interchange; or,
Accompany it with the information you received as to the offer to
 distribute corresponding source code. (This alternative is allowed only
 for noncommercial distribution and only if you received the program in
 object code or executable form with such an offer, in accord with
 Subsection b above.)
The source code for a work means the preferred form of the work for
 making modifications to it. For an executable work, complete source
 code means all the source code for all modules it contains, plus any
 associated interface definition files, plus the scripts used to control
 compilation and installation of the executable. However, as a special
 exception, the source code distributed need not include anything that
 is normally distributed (in either source or binary form) with the
 major components (compiler, kernel, and so on) of the operating system
 on which the executable runs, unless that component itself accompanies
 the executable.
If distribution of executable or object code is made by offering
 access to copy from a designated place, then offering equivalent access
 to copy the source code from the same place counts as distribution of
 the source code, even though third parties are not compelled to copy
 the source along with the object code.
You may not copy, modify, sublicense, or distribute the Program
 except as expressly provided under this License. Any attempt otherwise
 to copy, modify, sublicense or distribute the Program is void, and will
 automatically terminate your rights under this License. However,
 parties who have received copies, or rights, from you under this
 License will not have their licenses terminated so long as such parties
 remain in full compliance.
You are not required to accept this License, since you have not
 signed it. However, nothing else grants you permission to modify or
 distribute the Program or its derivative works. These actions are
 prohibited by law if you do not accept this License. Therefore, by
 modifying or distributing the Program (or any work based on the
 Program), you indicate your acceptance of this License to do so, and
 all its terms and conditions for copying, distributing or modifying the
 Program or works based on it.
Each time you redistribute the Program (or any work based on the
 Program), the recipient automatically receives a license from the
 original licensor to copy, distribute or modify the Program subject to
 these terms and conditions. You may not impose any further restrictions
 on the recipients' exercise of the rights granted herein. You are not
 responsible for enforcing compliance by third parties to this License.
If, as a consequence of a court judgment or allegation of patent
 infringement or for any other reason (not limited to patent issues),
 conditions are imposed on you (whether by court order, agreement or
 otherwise) that contradict the conditions of this License, they do not
 excuse you from the conditions of this License. If you cannot
 distribute so as to satisfy simultaneously your obligations under this
 License and any other pertinent obligations, then as a consequence you
 may not distribute the Program at all. For example, if a patent license
 would not permit royalty-free redistribution of the Program by all
 those who receive copies directly or indirectly through you, then the
 only way you could satisfy both it and this License would be to refrain
 entirely from distribution of the Program.
If any portion of this section is held invalid or unenforceable under
 any particular circumstance, the balance of the section is intended to
 apply and the section as a whole is intended to apply in other
 circumstances.
It is not the purpose of this section to induce you to infringe any
 patents or other property right claims or to contest validity of any
 such claims; this section has the sole purpose of protecting the
 integrity of the free software distribution system, which is
 implemented by public license practices. Many people have made generous
 contributions to the wide range of software distributed through that
 system in reliance on consistent application of that system; it is up
 to the author/donor to decide if he or she is willing to distribute
 software through any other system and a licensee cannot impose that
 choice.
This section is intended to make thoroughly clear what is believed to
 be a consequence of the rest of this License.
If the distribution and/or use of the Program is restricted in
 certain countries either by patents or by copyrighted interfaces, the
 original copyright holder who places the Program under this License may
 add an explicit geographical distribution limitation excluding those
 countries, so that distribution is permitted only in or among countries
 not thus excluded. In such case, this License incorporates the
 limitation as if written in the body of this License.
The Free Software Foundation may publish revised and/or new versions
 of the General Public License from time to time. Such new versions will
 be similar in spirit to the present version, but may differ in detail
 to address new problems or concerns.
Each version is given a distinguishing version number. If the Program
 specifies a version number of this License which applies to it and "any
 later version", you have the option of following the terms and
 conditions either of that version or of any later version published by
 the Free Software Foundation. If the Program does not specify a version
 number of this License, you may choose any version ever published by
 the Free Software Foundation.
If you wish to incorporate parts of the Program into other free
 programs whose distribution conditions are different, write to the
 author to ask for permission. For software which is copyrighted by the
 Free Software Foundation, write to the Free Software Foundation; we
 sometimes make exceptions for this. Our decision will be guided by the
 two goals of preserving the free status of all derivatives of our free
 software and of promoting the sharing and reuse of software generally.
NO WARRANTY
BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
 FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
 OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
 PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
 EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE
 ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH
 YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
 NECESSARY SERVICING, REPAIR OR CORRECTION.
IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
 WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY
 AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU
 FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR
 CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE
 PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
 RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
 FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF
 SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
 DAMAGES.
END OF TERMS AND CONDITIONS
How to Apply These Terms to Your New Programs
If you develop a new program, and you want it to be of the greatest
 possible use to the public, the best way to achieve this is to make it
 free software which everyone can redistribute and change under these
 terms.
To do so, attach the following notices to the program. It is safest
 to attach them to the start of each source file to most effectively
 convey the exclusion of warranty; and each file should have at least
 the "copyright" line and a pointer to where the full notice is found.
one line to give the program's name and an idea of what it does.Copyright (C) 
yyyy  name of authorThis program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
Also add information on how to contact you by electronic and paper
 mail.
If the program is interactive, make it output a short notice like
 this when it starts in an interactive mode:
Gnomovision version 69, Copyright (C) 
year name of authorGnomovision comes with ABSOLUTELY NO WARRANTY; for details
type `show w'.  This is free software, and you are welcome
to redistribute it under certain conditions; type `show c' 
for details.
The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of
 course, the commands you use may be called something other than 
`show w'
 and `show c'; they could even be
 mouse-clicks or menu items--whatever suits your program.
You should also get your employer (if you work as a programmer) or
 your school, if any, to sign a "copyright disclaimer" for the program,
 if necessary. Here is a sample; alter the names:
Yoyodyne, Inc., hereby disclaims all copyright
interest in the program `Gnomovision'
(which makes passes at compilers) written 
by James Hacker.
signature of Ty Coon, 1 April 1989
Ty Coon, President of Vice
GNU LIBRARY GENERAL PUBLIC LICENSE 
Version 2, June 1991
Copyright (C) 1991 Free Software Foundation, Inc.
59 Temple Place - Suite 330, Boston, MA  02111-1307, USA
Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
[This is the first released version of the library GPL.  It is
 numbered 2 because it goes with version 2 of the ordinary GPL.]
Preamble 
The licenses for most software are designed to take away your freedom
 to share and change it. By contrast, the GNU General Public Licenses
 are intended to guarantee your freedom to share and change free
 software--to make sure the software is free for all its users.
This license, the Library General Public License, applies to some
 specially designated Free Software Foundation software, and to any
 other libraries whose authors decide to use it. You can use it for your
 libraries, too.
When we speak of free software, we are referring to freedom, not
 price. Our General Public Licenses are designed to make sure that you
 have the freedom to distribute copies of free software (and charge for
 this service if you wish), that you receive source code or can get it
 if you want it, that you can change the software or use pieces of it in
 new free programs; and that you know you can do these things.
To protect your rights, we need to make restrictions that forbid
 anyone to deny you these rights or to ask you to surrender the rights.
 These restrictions translate to certain responsibilities for you if you
 distribute copies of the library, or if you modify it.
For example, if you distribute copies of the library, whether gratis
 or for a fee, you must give the recipients all the rights that we gave
 you. You must make sure that they, too, receive or can get the source
 code. If you link a program with the library, you must provide complete
 object files to the recipients so that they can relink them with the
 library, after making changes to the library and recompiling it. And
 you must show them these terms so they know their rights.
Our method of protecting your rights has two steps: (1) copyright the
 library, and (2) offer you this license which gives you legal
 permission to copy, distribute and/or modify the library.
Also, for each distributor's protection, we want to make certain that
 everyone understands that there is no warranty for this free library.
 If the library is modified by someone else and passed on, we want its
 recipients to know that what they have is not the original version, so
 that any problems introduced by others will not reflect on the original
 authors' reputations.
Finally, any free program is threatened constantly by software
 patents. We wish to avoid the danger that companies distributing free
 software will individually obtain patent licenses, thus in effect
 transforming the program into proprietary software. To prevent this, we
 have made it clear that any patent must be licensed for everyone's free
 use or not licensed at all.
Most GNU software, including some libraries, is covered by the
 ordinary GNU General Public License, which was designed for utility
 programs. This license, the GNU Library General Public License, applies
 to certain designated libraries. This license is quite different from
 the ordinary one; be sure to read it in full, and don't assume that
 anything in it is the same as in the ordinary license.
The reason we have a separate public license for some libraries is
 that they blur the distinction we usually make between modifying or
 adding to a program and simply using it. Linking a program with a
 library, without changing the library, is in some sense simply using
 the library, and is analogous to running a utility program or
 application program. However, in a textual and legal sense, the linked
 executable is a combined work, a derivative of the original library,
 and the ordinary General Public License treats it as such.
Because of this blurred distinction, using the ordinary General
 Public License for libraries did not effectively promote software
 sharing, because most developers did not use the libraries. We
 concluded that weaker conditions might promote sharing better.
However, unrestricted linking of non-free programs would deprive the
 users of those programs of all benefit from the free status of the
 libraries themselves. This Library General Public License is intended
 to permit developers of non-free programs to use free libraries, while
 preserving your freedom as a user of such programs to change the free
 libraries that are incorporated in them. (We have not seen how to
 achieve this as regards changes in header files, but we have achieved
 it as regards changes in the actual functions of the Library.) The hope
 is that this will lead to faster development of free libraries.
The precise terms and conditions for copying, distribution and
 modification follow. Pay close attention to the difference between a
 "work based on the library" and a "work that uses the library". The
 former contains code derived from the library, while the latter only
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That's all there is to it!
B - Common Network Settings 
This appendix covers many of the popular TCP/IP network interfaces
 and printer servers available on the market today.
Configuring a Network Interface 
When you first install a network printer or print server on your LAN,
 you need to set the Internet Protocol ("IP") address. On most
 higher-end "workgroup" printers, you can set the address through the
 printer control panel. However, in most cases you will want to assign
 the addresses remotely from your workstation. This makes administration
 a bit easier and avoids assigning duplicate addresses accidentally.
To setup your printer or print server for remote address assignment,
 you'll need the Ethernet Media Access Control ("MAC") address, also
 sometimes called a node address, and the IP address you want to use for
 the device. The Ethernet MAC address can often be found on the printer
 test page or bottom of the print server.
Configuring the IP Address Using ARP 
The easiest way to set the IP address of a network device is to use
 the 
arp(8) command. The arp sends an Address
 Resolution Protocol ("ARP") packet to the specified Ethernet MAC
 address, setting the network device's IP address:
arp -s ip-address ethernet-address ENTERarp -s host.domain.com 08:00:69:00:12:34 ENTERarp -s 192.0.2.2 08:00:69:00:12:34 ENTER Configuring the IP Address Using RARP 
The most flexible way to remotely assign IP addresses under UNIX is
 through the Reverse Address Resolution Protocol ("RARP"). RARP allows a
 network device to request an IP address using its Ethernet MAC address,
 and one or more RARP servers on the network will respond with an ARP
 packet with the IP address the device can use.
RARP should be used when you have to manage many printers or print
 servers, or when you have a network device that does not remember its
 IP address after a power cycle. If you just have a single printer or
 print server, the 
arp command is the way to go.
Some UNIX operating systems use a program called rarpd(8) to manage RARP. Others, like Linux, support this protocol in the
 kernel. For systems that provide the 
rarpd program you
 will need to start it before RARP lookups will work:
rarpd ENTERUnder IRIX you can enable this functionality by default using:
chkconfig rarpd on ENTERBoth the rarpd program and kernel RARP support read a
 list of Ethernet and IP addresses from the file
 /etc/ethers.
 Each line contains the Ethernet address (colon delimited) followed by
 an IP address or hostname like:
08:00:69:00:12:34 myprinter.mydomain.com
08:00:69:00:12:34 192.0.2.2
Add a line to this file and cycle the power on the printer or print
 server to set its address.
Configuring the IP Address Using BOOTP 
The BOOTP protocol is used when you need to provide additional
 information such as the location of a configuration file to the network
 interface. Using the standard 
bootpd(8) program supplied
 with UNIX you simply need to add a line to the
 /etc/bootptab file; for IRIX:
myprinter 08:00:69:00:12:34 192.0.2.2 
myprinter.bootNewer versions of bootpd use a different format:
myprinter:ha=080069001234:ip=192.0.2.2:
t144=myprinter.bootThe myprinter.boot file resides in the /usr/local/boot
 directory by default. If you do not need to
 provide a boot file you may leave the last part of the line blank.
 NOTE:Some versions of UNIX do not enable the BOOTP service by default. The /etc/inetd.conf
 usually contains a line for the BOOTP service
 that can be uncommented if needed.
Verifying the Printer Connection 
To test that the IP address has been successfully assigned and that
 the printer is properly connected to your LAN, type:
ping ip-address ENTERIf the connection is working properly you will see something like:
ping myprinter ENTERPING myprinter (192.0.2.2): 56 data bytes
64 bytes from 192.0.2.2: icmp_seq=0 ttl=15 time=5 ms
64 bytes from 192.0.2.2: icmp_seq=1 ttl=15 time=3 ms
64 bytes from 192.0.2.2: icmp_seq=2 ttl=15 time=3 ms
64 bytes from 192.0.2.2: icmp_seq=3 ttl=15 time=3 ms
If not, verify that the printer or print server is connected to the
 LAN, it is powered on, the LAN cabling is good, and the IP address is
 set correctly. You can usually see the current IP address and network
 status by printing a configuration or test page on the device.
Common Network Interface Settings 
Once you have set the IP address you can access the printer or print
 server using the 
ipp, lpd, or socket backends. The following is a list of common network interfaces and
 printer servers and the settings you should use with CUPS:
Model/ManufacturerDevice
 URI(s)
Apple LaserWriter lpd://address
/PASSTHRU Axis w/o IPP
 #AXIS(see directions) socket://address:9100
 socket://address:9101
 socket://address:9102 Axis w/IPP ipp://address/LPT1
 ipp://address/LPT2
 ipp://address/COM1 Castelle LANpressTM lpd://
address/pr1
 lpd://address/pr2
 lpd://address/pr3 DPI NETPrint lpd://address/pr1
 lpd://address/pr2
 lpd://address/pr3 EFI® Fiery® RIP lpd://address
/print EPSON® Multiprotocol Ethernet
 Interface Board
socket://address Extended System ExtendNET lpd://
address/pr1
 lpd://address/pr2
 lpd://address/pr3 Hewlett Packard JetDirect w/o IPP socket://
address:9100
 socket://address:9101
 socket://address:9102 Hewlett Packard JetDirect w/IPP ipp://
address/ipp
 ipp://address/ipp/port1
 ipp://address/ipp/port2
 ipp://address/ipp/port3 Intel® NetportExpress XL, PRO/100 lpd://
address/LPT1_PASSTHRU
 lpd://address/LPT2_PASSTHRU
 lpd://address/COM1_PASSTHRU LexmarkTM MarkNet lpd://
address/ps Linksys EtherFast®
 #LINKSYS(see directions) socket://address:4010
 socket://address:4020
 socket://address:4030 Kodak® lpd://address/ps QMS® CrownNetTM lpd://
address/ps Tektronix® PhaserShareTM socket://
address:9100 XEROX® 4512 NIC lpd://address
/PORT1 XEROX® XNIC lpd://address/PASSTHRU
XEROX® (most others) socket://address
:5503 
Configuring Axis Print Servers 
The Axis print servers can be configured using ARP, RARP, or BOOTP.
 However, on models that do not provide IPP support an additional step
 must be performed to configure the TCP/IP portion of the print server
 for use with CUPS.
Each print server contains a configuration file named config that contains a list of network parameters used by the server. To
 modify this file you must first download it from the print server using
 the 
ftp(1) program:
ftp ip-address ENTERConnected to ip-address.
220 Axis NPS ### FTP Printer Server V#.## MON DD YEAR ready.
ftp> 
user root ENTER331 User name ok, need password
Password: 
pass ENTER (this is not echoed)230 User logged in
ftp> 
get config ENTERlocal: config remote: config
200 PORT command successful.
150 Opening data connection for config (192,0,2,2),
(mode ascii).
226 Transfer complete.
##### bytes received in #.## seconds (##### Kbytes/s)
ftp> 
quit ENTER221 Goodbye.
Next, edit the file with your favorite text editor and locate the
 lines beginning with:
RTN_OPT.     : YES
RTEL_PR1.    : 0
RTEL_PR2.    : 0
RTEL_PR3.    : 0
RTEL_PR4.    : 0
RTEL_PR5.    : 0
RTEL_PR6.    : 0
RTEL_PR7.    : 0
RTEL_PR8.    : 0
 Change the 
RTN_OPT line to read:
RTN_OPT.     : 
NOThis disables the Reverse TELNET protocol and enables the standard
 TELNET protocol on the print server. Next, assign a port number for
 each parallel and serial port on the server as follows:
RTEL_PR1.    : 
9100RTEL_PR2.    : 
9101RTEL_PR3.    : 
9102RTEL_PR4.    : 
9103RTEL_PR5.    : 
9104RTEL_PR6.    : 
9105RTEL_PR7.    : 
9106RTEL_PR8.    : 
9107This essentially makes the Axis print server look like a Hewlett
 Packard JetDirect EX print server. Save the file and then upload the
 new
 config file using the ftp command:
ftp ip-address ENTERConnected to ip-address.
220 Axis NPS ### FTP Printer Server V#.## MON DD YEAR ready.
ftp> 
user root ENTER331 User name ok, need password
Password: 
pass ENTER (this is not echoed)230 User logged in
ftp> 
put config CONFIG ENTERlocal: config remote: CONFIG
200 PORT command successful.
150 Opening data connection for config (192,0,2,2), (mode ascii).
226 Transfer complete.
##### bytes received in #.## seconds (##### Kbytes/s)
ftp> 
get hardreset ENTERlocal: hardreset remote: hardreset
200 PORT command successful.
421 Axis NPS ### hard reset, closing connection.
ftp> 
quit ENTER221 Goodbye.
Your Axis print server is now ready for use!
Configuring Linksys Print Servers 
The Linksys print servers can be configured using ARP, RARP, or
 BOOTP. Like older Axis print servers, an additional step must be
 performed to configure the TCP/IP portion of the print server for use
 with CUPS.
Each print server contains a configuration file named CONFIG that contains a list of network parameters used by the server. To
 modify this file you must first download it from the print server using
 the 
ftp(1) program:
ftp -n ip-address ENTERConnected to ip-address.
220 Print Server Ready.
Remote system type is Print.
ftp> 
get CONFIG ENTERlocal: CONFIG remote: CONFIG
200 Command OK.
150 Open ASCII Mode Connection.
WARNING! 68 bare linefeeds received in ASCII mode
File may not have transferred correctly.
226 Transfer complete.
##### bytes received in #.## seconds (##### Kbytes/s)
ftp> 
quit ENTER221 Goodbye.
Next, edit the file with your favorite text editor and locate the
 lines beginning with:
0100 L1_PROUT:P1
0120 L2_PROUT:P1
0140 L3_PROUT:P1
Change the port number for each parallel and serial port on the
 server as follows:
0100 L1_PROUT:
P10120 L2_PROUT:
P20140 L3_PROUT:
P3This maps each virtual printer with a physical port. Save the file
 and then upload the new
 CONFIG file using the ftp command:
ftp -n ip-address ENTERConnected to ip-address.
220 Print Server Ready.
Remote system type is Print.
ftp> 
put CONFIG ENTERlocal: CONFIG remote: CONFIG
200 Command OK.
150 Open ASCII Mode Connection.
226 Transfer complete.
##### bytes received in #.## seconds (##### Kbytes/s)
ftp> 
quit ENTER221 Goodbye.
Your Linksys print server is now ready for use!
Configuring LPD Printing Options 
The LPD backend supports several options which are included in the
 device URI, e.g.:
    lpd://server/name?option1=value1+option2=value2+...+optionN=valueN
The following table summarizes the options and values that are
 supported:
Option=ValueDescription banner=off
 banner=no
 banner=false Does not request a LPD banner
 page for the job. (Default)
banner=on
 banner=yes
 banner=true Requests a LPD banner page for the
 job.
format=c
 format=d
 format=f
 format=g
 format=l
 format=n
 format=o
 format=p
 format=r
 format=t
 format=v Specifies the LPD format code of the
 print job. "format=l" is raw output, while "format=o" is PostScript.
 (Default is "format=l" for raw output)
manual_copies=off
 manual_copies=no
 manual_copies=false Specifies that the backend
 should not send multiple copies of a print job in the print data file.
manual_copies=on
 manual_copies=yes
 manual_copies=true Specifies that the backend
 should send multiple copies of a print job in the print data file to
 print more than one copy. (Default)
order=control,data Specifies that the LPD
 control file should be sent before the print data file. (Default)
order=data,control= Specifies that the
 print data file should be sent before the LPD control file.
reserve=off
 reserve=no
 reserve=false Specifies that the backend
 should not reserve a priviledged source port as required by RFC 1179.
reserve=on
 reserve=yes
 reserve=true
 reserve=rfc1179 Specifies that the backend
 should reserve a priviledges source port from 721 to 731 inclusive as
 required by RFC 1179. This option may cause reduced printing
 performance when more than 11 LPD printers are defined on the server
 due to port contention issues.
reserve=any Specifies that the backend
 should reserve a priviledges source port from 1 to 1023 inclusive. This
 often works with LPD implementations that require a priviledged source
 port but do not limit it to the range defined by RFC 1179, allowing for
 more printers to be active at the same time. (Default)
sanitize_title=off
 sanitize_title=no
 sanitize_title=false Specifies that the
 backend should not sanitize the job title string. (Default on OSX)
sanitize_title=on
 sanitize_title=yes
 sanitize_title=true Specifies that the backend
 should sanitize the job title string. (Default on all but OSX)
timeout=N Specifies the response timeout
 for all LPD commands and transactions in seconds. (Default is 300
 seconds)
C - Printer Drivers 
This appendix lists the printer drivers that are provided with CUPS.
Printer Drivers 
CUPS includes the following printer drivers:
#DYMODYMO Label Printer , dymo.ppd #EPSON9EPSON 9-pin Dot Matrix , epson9.ppd #EPSON24EPSON 24-pin Dot Matrix , epson24.ppd #STCOLOREPSON Stylus Color , stcolor.ppd #STPHOTOEPSON Stylus Photo , stphoto.ppd #DESKJETHP DeskJet , deskjet.ppd #LASERJETHP LaserJet , laserjet.ppd DYMO Label Printer 
The DYMO Label Printer driver (dymo.ppd) supports the DYMO
 LabelWriter 300 series (300/310/315/320/330/330 Turbo) thermal label
 printers. It provides 136, 203, and 300 DPI output in black only.
EPSON 9-pin Dot Matrix 
The EPSON 9-pin Dot Matrix driver (epson9.ppd) supports
 9-pin dot matrix printers that implement the ESC/P command set. It
 provides 60x72, 120x72, and 240x72 DPI output in black only.
EPSON 24-pin Dot Matrix 
The EPSON 24-pin Dot Matrix driver (epson9.ppd) supports
 24-pin dot matrix printers that implement the ESC/P command set. It
 provides 120x180, 180x180, 360x180, and 360x360 DPI output in black
 only.
EPSON Stylus Color 
The EPSON Stylus Color driver (stcolor.ppd) supports EPSON
 Stylus Color printers that implement the ESC/P2 command set. It
 provides 180, 360, and 720 DPI output in black and color (CMYK).
EPSON Stylus Photo 
The EPSON Stylus Photo driver (stphoto.ppd) supports EPSON
 Stylus Photo printers that implement the ESC/P2 command set. It
 provides 180, 360, and 720 DPI output in black and color (CMYKcm).
HP DeskJet 
The HP DeskJet driver (deskjet.ppd) supports HP DeskJet
 printers that implement the PCL command set. It provides 150, 300, and
 600 DPI output in black and color (CMYK).
The DeskJet printers that implement the HP-PPA command set (720C,
 722C, 820C, and 1100C) are
 not supported due to a complete lack
 of documentation and support from Hewlett Packard.
The duplexer provided with the HP DeskJet 900 series printers is also
 not supported for similar reasons.
HP LaserJet 
The HP LaserJet driver (laserjet.ppd) supports HP LaserJet
 printers that implement the PCL command set. It provides 150, 300, and
 600 DPI output in black only and supports the duplexer if installed.
LaserJet printers that do not implement PCL (3100, 3150) are not
 supported due to a complete lack of documentation and support from
 Hewlett Packard.
D - List of Files 
This appendix lists the files and directories that are installed for
 the Common UNIX Printing System.
PathnameDescription /etc/cups/certs/ The location of
 authentication certificate files for local HTTP clients.
/etc/cups/classes.conf The printer classes
 configuration file for the scheduler.
/etc/cups/cupsd.conf The scheduler
 configuration file.
/etc/cups/interfaces/ The location of
 System V interface scripts for printers.
/etc/cups/mime.convs The list of standard
 file filters included with CUPS.
/etc/cups/mime.types The list of recognized
 file types for CUPS.
/etc/cups/ppd/ The location of PostScript
 Printer Description ("PPD") files for printers.
/etc/cups/printers.conf The printer
 configuration file for the scheduler.
/usr/bin/cancel The System V cancel job(s)
 command.
/usr/bin/disable The System V disable
 printer command.
/usr/bin/enable The System V enable printer
 command.
/usr/bin/lp The System V print command. /usr/bin/lpoptions Sets user-defined
 printing options and defaults.
/usr/bin/lppasswd Adds, changes, or removes
 Digest password accounts.
/usr/bin/lpq The Berkeley status command. /usr/bin/lpr The Berkeley print command. /usr/bin/lprm The Berkeley cancel job(s)
 command.
/usr/bin/lpstat The System V status
 command.
/usr/include/cups/ CUPS API header files. /usr/lib32/libcups.a
 /usr/lib32/libcupsimage.a Static libraries (IRIX 6.5) /usr/lib/libcups.a
 /usr/lib/libcupsimage.a Static libraries (all others) /usr/lib/libcups.sl.2
 /usr/lib/libcupsimage.sl.2 Shared libraries (HP-UX) /usr/lib32/libcups.so.2
 /usr/lib32/libcupsimage.so.2 Shared libraries (IRIX 6.5) /usr/lib/libcups.so.2
 /usr/lib/libcupsimage.so.2 Shared libraries (all others) /usr/libexec/cups/backend/ Backends for
 various types of printer connections (*BSD and OSX)
/usr/lib/cups/backend/ Backends for various
 types of printer connections (all others)
/usr/libexec/cups/cgi-bin/ CGI programs for
 the scheduler (*BSD and OSX)
/usr/lib/cups/cgi-bin/ CGI programs for the
 scheduler (all others)
/usr/libexec/cups/daemon/ Daemons for
 polling and LPD support (*BSD and OSX)
/usr/lib/cups/daemon/ Daemons for polling
 and LPD support (all others)
/usr/libexec/cups/filter/ Filters for
 various types of files (*BSD and OSX)
/usr/lib/cups/filter/ Filters for various
 types of files (all others)
/usr/lib/locale/ The location of
 language-specific message files. (System V)
/usr/lib/nls/msg/ The location of
 language-specific message files. (Compaq Tru64 UNIX)
/usr/share/locale/ The location of
 language-specific message files. (Linux, *BSD)
/usr/sbin/accept The accept-jobs command. /usr/sbin/cupsd The CUPS print scheduler. /usr/sbin/lpadmin The System V printer
 administration tool.
/usr/sbin/lpc The Berkeley printer
 administration tool.
/usr/sbin/lpinfo The get-devices and
 get-ppds command.
/usr/sbin/lpmove The move-jobs command. /usr/sbin/reject The reject-jobs command. /usr/share/catman/a_man/
 /usr/share/catman/u_man/ Man pages (IRIX) /usr/share/man/ Man pages (Compaq Tru64
 UNIX, HP-UX, Solaris)
/usr/man/ Man pages (all others) /usr/share/cups/data/ The location of
 filter data files.
/usr/share/cups/data/testprint.ps The
 PostScript test page file.
/usr/share/cups/fonts/ The location of
 PostScript fonts for the PostScript RIP.
/usr/share/cups/model/ The location of
 PostScript Printer Description ("PPD") files and interface scripts that
 may be used to setup a printer queue.
/usr/share/cups/pstoraster/ Other
 PostScript RIP initialization files.
/usr/share/cups/pstoraster/Fontmap The font
 mapping file (converts filenames to fontnames)
/usr/share/cups/templates/ The location of
 HTML template files for the web interfaces.
/usr/share/doc/cups/ Documentation and web
 page data for the scheduler.
/var/log/cups/ The location of scheduler
 log files.
/var/spool/cups/ The location of print
 files waiting to be printed.
E - Troubleshooting Common Problems 
This appendix covers some of the common problems first-time users
 encounter when installing and configuring CUPS.
Commercial support for CUPS is available from Easy Software Products.
 For more information please contact us at:
WWW: http://www.easysw.com/cups/ http://www.easysw.com/cups/
EMail: mailto:info@easysw.cominfo@easysw.com Telephone (M-F, 9-5 EST): +1.301.373.9600 My Applications Don't See the Available Printers 
Many applications read the /etc/printcap file to get a
 list of available printers.
The default CUPS configuration creates the /etc/printcap file automatically. To enable or disable automatic creation and
 updating of this file, use the 
#PrintcapPrintcap  directive described in #PRINTING_MANAGEMENTChapter 6,
 "Printing System Management"
.
CUPS Doesn't Recognize My Username or Password! 
CUPS will ask you for a UNIX username and password when you perform
 printer administration tasks remotely or via a web browser. The default
 configuration requires that you use the 
root username and
 the corresponding password to authenticate the request.
CUPS does not allow you to authenticate an administration request
 with an account that has no password for security reasons. If you do
 not have a password on your 
root account then you won't be
 able to add printers remotely or via the web interface!
To disable password authentication you need to edit the /etc/cups/cupsd.conf
 file and comment out the lines reading:
AuthType Basic
AuthClass System
for the /admin location. Then restart the CUPS server as
 described in 
#PRINTING_MANAGEMENTChapter 6, "Printing System
 Management"
.
 NOTE:Disabling password checks will allow any local user to change your
 printer and class configuration, but remote administration from another
 machine will still not be allowed.
I Can't Do Administration Tasks from Another
 Machine!
The default CUPS configuration limits administration to the local
 machine. To open up access, edit the
 /etc/cups/cupsd.conf and comment out the lines reading:
Order deny,allow
Deny from all
Allow from 127.0.0.1
for the /admin location. Then restart the CUPS server as
 described in 
#PRINTING_MANAGEMENTChapter 6, "Printing System
 Management"
.
 NOTE:Allowing administration access from all hosts is a potential security
 risk. Please read 
#PRINTING_SECURITYChapter 6, "Printing
 System Management"
 for a description of these risks and ways to
 minimize them.
I Can't Do Administration Tasks from My Web Browser! 
This problem is usually caused by:
not specifying the correct password for the root account.accessing the CUPS server using the hostname or IP address of the
 server without enabling remote access for administration functions.
 This can be corrected by following the instructions in the 
#ALLOW_REMOTE"I Can't Do Administration Tasks from Another Machine!"
 section
 earlier in this appendix.
not setting a password on the root account. CUPS will not
 authenticate a user account that does not have a password for security
 reasons.
authenticating using an account other than root, but the account you
 are using is not a member of the system group.
configuring CUPS to use Digest authentication, but your web browser
 does not support Digest authentication.
Connection Refused Messages 
Under normal circumstances, "connection refused" messages for a
 networked printer should be expected from time to time. Most network
 interfaces only allow a single connection to be made at any given time
 (one job at a time) and will refuse access to all other systems while
 the first connection is active. CUPS automatically retries the
 connection once every 30 seconds.
If the problem persists and you are unable to print any jobs to the
 printer, verify that another machine is not maintaining a connection
 with the printer, and that you have selected the proper port or printer
 name for the printer.
Also, most external print servers will refuse connections if the
 connected printer is turned off or is off-line. Verify that the
 affected printer is turned on and is online.
Write Error Messages 
If you get "write error" messages on a printer queue the printer
 interface (usually a Hewlett Packard JetDirect interface) has timed out
 and reset the network connection from your workstation.
The error is caused by that startup delay between the initial setup
 of the printer or plotter and the first page of print data that is
 sent.
To correct the problem, change the idle timeout on the interface to
 at least 180 seconds or 3 minutes. To change the timeout on a Hewlett
 Packard JetDirect interface, type:
telnet ip-address ENTERTrying ip-address...
Connected to ip-address.
Escape character is `^]'.
Please type [Return] two times, to initialize telnet configuration
For HELP type "?"
> 
idle-timeout: 180 ENTER> 
quit ENTER