SUSE® Linux Enterprise Server

Storage Administration Guide

12/15/2010

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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. Additional Information
2. What’s New
2.1. What’s New in SLES 11 SP1
2.2. 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. Direct LVM Management
4.7. Resizing an LVM Partition
5. Resizing File Systems
5.1. Guidelines for Resizing
5.2. Increasing an Ext2 or Ext3 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. Tuning the Failover for Specific Host Bus Adapters
7.8. Configuring Multipath I/O for the Root Device
7.9. Configuring Multipath I/O for an Existing Software RAID
7.10. Scanning for New Devices without Rebooting
7.11. Scanning for New Partitioned Devices without Rebooting
7.12. Viewing Multipath I/O Status
7.13. Managing I/O in Error Situations
7.14. Resolving Stalled I/O
7.15. Additional Information
7.16. What’s Next
8. Software RAID Configuration
8.1. Understanding RAID Levels
8.2. Soft RAID Configuration with YaST
8.3. Troubleshooting
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
14. Volume Snapshots
14.1. Understanding Volume Snapshots
14.2. Creating Linux Snapshots with LVM
14.3. Monitoring a Snapshot
14.4. Deleting Linux Snapshots
15. Troubleshooting Storage Issues
15.1. Is DM-MPIO Available for the Boot Partition?
A. Documentation Updates
A.1. May 2010 (SLES 11 SP1)
A.2. February 23, 2010
A.3. January 20, 2010
A.4. December 1, 2009
A.5. October 20, 2009
A.6. August 3, 2009
A.7. June 22, 2009
A.8. May 21, 2009

List of Figures

4.1. Physical Partitioning versus LVM
4.2. Creating a Volume Group
4.3. Physical Volume Setup
4.4. Logical Volume Management
4.5. Creating Logical Volumes
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

List of Tables

1.1. File System Types in Linux
1.2. Maximum Sizes of 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. Group Policy Options for the multipath -p Command
7.5. Multipath Attributes
7.6. 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