SUSE® Linux Enterprise Server

Storage Administration Guide

Publication Date 04 Feb 2011

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EVMS User Guide, January 18, 2005
Copyright © 2005 IBM
License Information
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Contents

About This Guide
1. Overview of EVMS
1.1. Benefits of EVMS
1.2. Plug-In Layers
1.3. Supported File Systems
1.4. Terminology
1.5. Location of Device Nodes for EVMS Storage Objects
2. Using EVMS to Manage Devices
2.1. Configuring the System Device at Install to Use EVMS
2.2. Configuring an Existing System Device to Use EVMS
2.3. Configuring LVM Devices to Use EVMS
2.4. Using EVMS with iSCSI Volumes
2.5. Using the ELILO Loader Files (IA-64)
2.6. Starting EVMS
2.7. Starting the EVMS Management Tools
3. Using UUIDs to Mount Devices
3.1. Naming Devices with udev
3.2. Understanding UUIDs
3.3. Using UUIDs in the Boot Loader and /etc/fstab File (x86)
3.4. Using UUIDs in the Boot Loader and /etc/fstab File (IA64)
3.5. Additional Information
4. Managing EVMS Devices
4.1. Understanding Disk Segmentation
4.2. Initializing Disks
4.3. Removing the Segment Manager from a Device
4.4. Creating Disk Segments (or Partitions)
4.5. Configuring Mount Options for Devices
4.6. What’s Next
5. Managing Multipath I/O for Devices
5.1. Understanding Multipathing
5.2. Planning for Multipathing
5.3. Multipath Management Tools
5.4. Configuring the System for Multipathing
5.5. Enabling and Starting Multipath I/O Services
5.6. Configuring Path Failover Policies and Priorities
5.7. Configuring Multipath I/O for the Root Device
5.8. Configuring Multipath I/O for an Existing Software RAID
5.9. Scanning for New Devices without Rebooting
5.10. Scanning for New Partitioned Devices without Rebooting
5.11. Viewing Multipath I/O Status
5.12. Managing I/O in Error Situations
5.13. Resolving Stalled I/O
5.14. Additional Information
5.15. What’s Next
6. Managing Software RAIDs with EVMS
6.1. Understanding Software RAIDs on Linux
6.2. Creating and Configuring a Software RAID
6.3. Expanding a RAID
6.4. Adding or Removing a Spare Disk
6.5. Managing Disk Failure and RAID Recovery
6.6. Monitoring Status for a RAID
6.7. Deleting a Software RAID and Its Data
7. Managing Software RAIDs 6 and 10 with mdadm
7.1. Creating a RAID 6
7.2. Creating Nested RAID 10 Devices with mdadm
7.3. Creating a Complex RAID 10 with mdadm
7.4. Creating a Degraded RAID Array
8. Resizing Software RAID Arrays with mdadm
8.1. Understanding the Resizing Process
8.2. Increasing the Size of a Software RAID
8.3. Decreasing the Size of a Software RAID
9. Installing and Managing DRBD Services
9.1. Understanding DRBD
9.2. Installing DRBD Services
9.3. Configuring the DRBD Service
9.4. Testing the DRBD Service
9.5. Troubleshooting DRBD
9.6. Additional Information
10. Troubleshooting Storage Issues
10.1. Is DM-MP Available for the Boot Partition?
10.2. Rescue System Cannot Find Devices That Are Managed by EVMS
10.3. Volumes on EVMS Devices Do Not Appear After Reboot
10.4. Volumes on EVMS Devices Do Not Appear When Using iSCSI
10.5. Device Nodes Are Not Automatically Re-Created on Restart
A. Documentation Updates
A.1. January 2011
A.2. June 21, 2010
A.3. June 11, 2010
A.4. February 23, 2010
A.5. January 20, 2010
A.6. October 20, 2009
A.7. September 2, 2009 (SLES 10 SP3)
A.8. May 15, 2009
A.9. November 24, 2008
A.10. June 10, 2008
A.11. March 20, 2008 (SLES 10 SP2)

List of Tables

1.1. EVMS Plug-In Layers
1.2. EVMS Terms
1.3. Device Node Location
4.1. EVMS Segment Managers
4.2. Disk Segment Types
4.3. Fstab Options in YaST
5.1. Multipath I/O Features of Storage Arrays
5.2. Tools in the multipath-tools Package
5.3. Group Policy Options for the multipath -p Command
5.4. Comparison of Multipath Device Name Types
5.5. Group Policy Options for the multipath -p Command
5.6. Multipath Attributes
5.7. ALUA Priorities for Device Mapper Multipath
6.1. Comparison of Software RAIDs and Hardware RAIDs
6.2. RAID Levels Supported by EVMS
6.3. Read and Write Performance for RAIDs
6.4. Fault Tolerance for RAIDs
6.5. Configuration Options in EVMS
6.6. Recommended Number of Storage Objects to Use in the Software RAID
6.7. RAID 5 Algorithms
6.8. RAID Events in mdadm
7.1. Comparison of RAID 5 and RAID 6
7.2. RAID Levels Supported in EVMS
7.3. Scenario for Creating a RAID 10 (1+0) by Nesting
7.4. Scenario for Creating a RAID 10 (0+1) by Nesting
7.5. Complex vs. Nested RAID 10
7.6. Scenario for Creating a RAID 10 Using the mdadm RAID10 Option
8.1. File System Support for Resizing
8.2. Tasks Involved in Resizing a RAID
8.3. Scenario for Increasing the Size of Component Partitions
8.4. Scenario for Increasing the Size of Component Partitions

SUSE® Linux Enterprise Server Storage Administration Guide 10 SP3/SP4