Chapter 11. Managing Network Connections¶
Contents
To surf the Internet or send and receive e-mail messages, you must have configured an Internet connection with YaST. Depending on your environment, in YaST select whether to use NetworkManager. In GNOME, you can then establish Internet connections with NetworkManager or ifup.
For a list of criteria to help you decide whether to use NetworkManager, see Section 30.5: Managing Network Connections with NetworkManager and Section 25.1.2: Integration in Changing Operating Environments in the SUSE Linux Enterprise Desktop Deployment Guide.
11.1. Enabling or Disabling NetworkManager¶
In YaST, click +.
To enable NetworkManager, select .
To disable NetworkManager, select .
Click .
Set up your network card using either automatic configuration via DHCP or a static IP address. For more information about network configuration with YaST, refer to the respective section in Basic Networking in the SUSE Linux Enterprise Desktop Deployment Guide.
Click to close the window.
If you want to use a dial-up connection, configure your modem in +. To configure an internal or USB ISDN modem, select +. To configure an internal or USB DSL modem, select +
![[Note]](admon/note.png) | Configuration of WLAN Cards |
|---|---|
Configure supported wireless cards directly in NetworkManager. | |
11.2. NetworkManager and SCPM¶
NetworkManager cannot work together with System Configuration Profile Management (SCPM) if SCPM also manages the network configuration. If SCPM is enabled on your system and you want to use SCPM and NetworkManager at the same time, you must disable the network resource in the SCPM configuration. To disable the network resource in all your SCPM profiles:
11.3. Using GNOME NetworkManager Applet¶
If you have decided to use NetworkManager, the GNOME NetworkManager applet starts automatically with the desktop environment. If the applet is not running, you can start it with the nm-applet command. When it is running, an icon indicating the current network status is shown in the system tray. Depending on the state of the network connection, the panel icon changes appearance. If you are not sure what the icon means, hold your mouse over the icon until an explanation appears.
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A wired connection has been established.
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Currently there is no connection to the Internet.
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A wireless connection has been established. Blue bars indicate the strength of the signal. More blue bars means better signal strength.
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The connection is being established or terminated.
11.3.1. Connecting to Wired Networks¶
If your computer is connected to an existing network with a network cable, use the NetworkManager applet to choose the network connection.
Left-click the applet icon to show a menu with available networks. The currently used connection is selected in the menu.
To switch to another network, choose it from the list. To connect to an 802.1X protected wired network, select the appropriate menu item and enter all required information for your type of connection.
To switch off all network connections, both wired and wireless, right-click the applet icon and uncheck .
To get information about the current connection (including interface used, IP address, and hardware address), right-click the applet icon and select . In this dialog, you can also configure your network devices. To do so, click to open YaST where you can define a new connection.
11.3.2. Connecting to Wireless Networks¶
The signal strength of wireless networks is also shown in the menu. Encrypted wireless networks are marked with a shield icon.
Procedure 11.1. Connecting to a Wireless Network
To connect to a wireless network, left-click the applet icon and choose en entry from the list of available wireless networks.
If the network is encrypted, a dialog opens.
Choose the type of the network uses and enter the appropriate or .
To connect to a network that does not broadcast its service set identifier (ESSID) and therefore cannot be detected automatically, left-click the NetworkManager icon and choose .
In the dialog that opens, enter the ESSID and set encryption parameters if necessary.
To disable wireless networking, right-click the applet icon and uncheck . This can be very useful if you are on a plane or in any other environment where wireless networking is not allowed.
11.4. NetworkManager and Security¶
NetworkManager distinguishes two types of wireless connections, trusted and untrusted. A trusted connection is any network that you explicitly selected in the past. All others are untrusted. Trusted connections are identified by the name and MAC address of the access point. Using the MAC address ensures that you cannot use a different access point with the name of your trusted connection.
If no wired connection is available, NetworkManager scans for available wireless networks. If multiple trusted networks are found, the most recently used is automatically selected. If all are untrusted, NetworkManager waits for your selection.
If the encryption setting changes but the name and MAC address remain the same, NetworkManager attempt to connect, but it first asks you to confirm the new encryption settings and provide any updates, such as a new key.
In a system with a wireless connection only, NetworkManager does not automatically start the connection during boot. You must log in first to establish a connection. If you want to make a wireless connection accessible without login, configure the trusted connection with YaST. Only wireless connections configured with YaST are sufficiently credible for NetworkManager to use during boot.
If you switch to offline mode after using a wireless connection, NetworkManager removes the ESSID. This ensures that the card really is unassociated.
11.4.1. Configuring Your Wireless Card as an Access Point¶
If your wireless card supports access point mode, you can use NetworkManager for configuration.
Click .
Add the network name and set the encryption in the dialog.
![[Important]](admon/important.png)
Unprotected Wireless Networks Are a Security Risk If you set to
None, everybody can connect to your network, reuse your connectivity, and intercept your network connection. To restrict access to your access point and to secure your connection, use encryption. You can choose from various WEP and WPA–based encryptions. If you are not sure which technology is best for you, see Chapter 28: Wireless Communication, in the .
11.4.2. Using NetworkManager with VPN¶
NetworkManager supports several VPN technologies. To use them, first install NetworkManager support for your VPN technology. You can select from:
NovellVPN
OpenVPN
vpnc (Cisco)
VPN support is included in the NetworkManager-novellvpn, NetworkManager-openvpn, and NetworkManager-vpns packages.
Procedure 11.2. Configuring a VPN connection with NetworkManager ¶
Click the NetworkManager applet and select +.
Click , then click to start the wizard.
Select the type of VPN connection you want to create, then click .
Type a name for your configuration in the field.
Specify all required information for your type of connection.
For example, for an OpenVPN connection, enter and choose the way to authenticate from . Complete the other required options depending on the connection chosen.
Alternatively, load settings from a saved configuration file by pressing and choosing your saved configuration file in a standard file dialog.
Click .
After the VPN is configured, you can select it from . To close a VPN connection, click .
11.4.3. GNOME Keyring Manager and Novell CASA¶
If you do not want to enter your credentials anew each time you want to connect to an encrypted network, you can use GNOME Keyring Manager to store your credentials encrypted on the disk, secured by a master password. Whenever any GNOME application that uses GNOME Keyring needs to access passwords or credentials stored there, a check is made if the keyring is locked or not. If it is locked, you will be prompted for the master password to unlock the keyring. For more information about GNOME Keyring Manager, refer to Section 2.4.4, “Managing Keyrings”.
Another option is to use single sign-on with Novell CASA. Single Sign-on is a method of access control that enables users to authenticate once and thus gain access to the resources of multiple software systems. If Novell CASA is configured for your system, NetworkManager will not ask for an additional password to unlock GNOME Keyring Manager. Instead, the keyring will be unlocked automatically when the users logs in to the desktop. For more information about Novell CASA, refer to Section 2.4.5, “Using Single Sign-on with Novell CASA”.