Linux Enterprise Server 11 SP2

Storage Administration Guide

Publication Date 03 Feb 2012

Legal Notices

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or (at your option) version 1.3; with the Invariant Section being this copyright notice and license. A copy of the license version 1.2 is included in the section entitled “GNU Free Documentation License”.

All information found in this book has been compiled with utmost attention to detail. However, this does not guarantee complete accuracy. Neither Novell, Inc., SUSE LINUX Products GmbH, the authors, nor the translators shall be held liable for possible errors or the consequences thereof.

Trademarks

For Novell trademarks, see the Novell Trademark and Service Mark list.

Linux* is a registered trademark of Linus Torvalds. All other third party trademarks are the property of their respective owners.

A trademark symbol (®, ™, etc.) denotes a Novell trademark; an asterisk (*) denotes a third party trademark.

Contents

About This Guide

1. Overview of File Systems in Linux

1.1. Terminology
1.2. Major File Systems in Linux
1.3. Other Supported File Systems
1.4. Large File Support in Linux
1.5. Managing Devices with the YaST2 Partitioner
1.6. Additional Information

2. What’s New for Storage in SLES 11

2.1. What’s New in SLES 11 SP2
2.2. What’s New in SLES 11 SP1
2.3. What’s New in SLES 11

3. Planning a Storage Solution

3.1. Partitioning Devices
3.2. Multipath Support
3.3. Software RAID Support
3.4. File System Snapshots
3.5. Backup and Antivirus Support

4. LVM Configuration

4.1. Understanding the Logical Volume Manager
4.2. Creating LVM Partitions
4.3. Creating Volume Groups
4.4. Configuring Physical Volumes
4.5. Configuring Logical Volumes
4.6. Tagging LVM2 Storage Objects
4.7. Resizing a Volume Group
4.8. Resizing a Logical Volume with YaST
4.9. Resizing a Logical Volume with Commands
4.10. Deleting a Volume Group
4.11. Deleting an LVM Partition (Physical Volume)

5. Resizing File Systems

5.1. Guidelines for Resizing
5.2. Increasing the Size of an Ext2, Ext3, or Ext4 File System
5.3. Increasing the Size of a Reiser File System
5.4. Decreasing the Size of an Ext2 or Ext3 File System
5.5. Decreasing the Size of a Reiser File System

6. Using UUIDs to Mount Devices

6.1. Naming Devices with udev
6.2. Understanding UUIDs
6.3. Using UUIDs in the Boot Loader and /etc/fstab File (x86)
6.4. Using UUIDs in the Boot Loader and /etc/fstab File (IA64)
6.5. Additional Information

7. Managing Multipath I/O for Devices

7.1. Understanding Multipathing
7.2. Planning for Multipathing
7.3. Multipath Management Tools
7.4. Configuring the System for Multipathing
7.5. Enabling and Starting Multipath I/O Services
7.6. Configuring Path Failover Policies and Priorities
7.7. Configuring Multipath I/O for the Root Device
7.8. Configuring Multipath I/O for an Existing Software RAID
7.9. Scanning for New Devices without Rebooting
7.10. Scanning for New Partitioned Devices without Rebooting
7.11. Viewing Multipath I/O Status
7.12. Managing I/O in Error Situations
7.13. Resolving Stalled I/O
7.14. Troubleshooting MPIO
7.15. What’s Next

8. Software RAID Configuration

8.1. Understanding RAID Levels
8.2. Soft RAID Configuration with YaST
8.3. Troubleshooting Software RAIDs
8.4. For More Information

9. Configuring Software RAID for the Root Partition

9.1. Prerequisites for the Software RAID
9.2. Enabling iSCSI Initiator Support at Install Time
9.3. Enabling Multipath I/O Support at Install Time
9.4. Creating a Software RAID Device for the Root (/) Partition

10. Managing Software RAIDs 6 and 10 with mdadm

10.1. Creating a RAID 6
10.2. Creating Nested RAID 10 Devices with mdadm
10.3. Creating a Complex RAID 10 with mdadm
10.4. Creating a Degraded RAID Array

11. Resizing Software RAID Arrays with mdadm

11.1. Understanding the Resizing Process
11.2. Increasing the Size of a Software RAID
11.3. Decreasing the Size of a Software RAID

12. iSNS for Linux

12.1. How iSNS Works
12.2. Installing iSNS Server for Linux
12.3. Configuring iSNS Discovery Domains
12.4. Starting iSNS
12.5. Stopping iSNS
12.6. For More Information

13. Mass Storage over IP Networks: iSCSI

13.1. Installing iSCSI
13.2. Setting Up an iSCSI Target
13.3. Configuring iSCSI Initiator
13.4. Using iSCSI Disks when Installing
13.5. Troubleshooting iSCSI
13.6. Additional Information

14. Fibre Channel Storage over Ethernet Networks: FCoE

14.1. Installing FCoE and the YaST2 FCoE Client
14.2. Configuring FCoE Interfaces during the Installation
14.3. Managing FCoE Services with YaST
14.4. Configuring FCoE with Commands
14.5. Managing FCoE Instances with the FCoE Administration Tool
14.6. Setting Up Partitions for an FCoE Initiator Disk
14.7. Creating a File System on an FCoE Initiator Disk
14.8. Additional Information

15. Volume Snapshots

15.1. Understanding Volume Snapshots
15.2. Creating Linux Snapshots with LVM
15.3. Monitoring a Snapshot
15.4. Deleting Linux Snapshots

16. Managing Access Control Lists over NFSv4

17. Troubleshooting Storage Issues

17.1. Is DM-MPIO Available for the Boot Partition?
17.2. Issues for iSCSI
17.3. Issues for Multipath I/O
17.4. Issues for Software RAIDs

A. GNU Licenses

A.1. GNU General Public License
A.2. GNU Free Documentation License

B. Documentation Updates

B.1. January 18, 2012 (SLES 11 SP2)
B.2. July 12, 2011
B.3. June 14, 2011
B.4. May 5, 2011
B.5. January 2011
B.6. September 16, 2010
B.7. June 21, 2010
B.8. May 2010 (SLES 11 SP1)
B.9. February 23, 2010
B.10. December 1, 2009
B.11. October 20, 2009
B.12. August 3, 2009
B.13. June 22, 2009
B.14. May 21, 2009

List of Figures

4.1. Physical Partitioning versus LVM
4.2. Physical Volumes in the Volume Group Named Home
4.3. Logical Volume Management
8.1. RAID Partitions
8.2. File System Settings
12.1. iSNS Discovery Domains and Discovery Domain Sets
13.1. iSCSI SAN with an iSNS Server
14.1. Open Fibre Channel over Ethernet SAN

List of Tables

1.1. File System Types in Linux
1.2. Maximum Sizes of Files and File Systems (On-Disk Format)
5.1. File System Support for Resizing
7.1. Multipath I/O Features of Storage Arrays
7.2. Tools in the multipath-tools Package
7.3. Group Policy Options for the multipath -p Command
7.4. Comparison of Multipath Device Name Types
7.5. Group Policy Options for the multipath -p Command
7.6. Multipath Attributes
7.7. ALUA Priorities for Device Mapper Multipath
10.1. Comparison of RAID 5 and RAID 6
10.2. Nested RAID Levels
10.3. Scenario for Creating a RAID 10 (1+0) by Nesting
10.4. Scenario for Creating a RAID 10 (0+1) by Nesting
10.5. Complex vs. Nested RAID 10
10.6. Scenario for Creating a RAID 10 Using the mdadm RAID10 Option
11.1. File System Support for Resizing
11.2. Tasks Involved in Resizing a RAID
11.3. Scenario for Increasing the Size of Component Partitions
11.4. Scenario for Increasing the Size of Component Partitions