Red Hat Enterprise Linux 6

DM Multipath

DM Multipath Configuration and Administration

Edition 1

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This book provides information on using the Device-Mapper Multipath feature of Red Hat Enterprise Linux 6.
1. Audience
2. Related Documentation
3. We Need Feedback!
4. Document Conventions
4.1. Typographic Conventions
4.2. Pull-quote Conventions
4.3. Notes and Warnings
1. Device Mapper Multipathing
1.1. New and Changed Features
1.1.1. New and Changed Features for Red Hat Enterprise Linux 6.0
1.1.2. New and Changed Features for Red Hat Enterprise Linux 6.1
1.1.3. New and Changed Features for Red Hat Enterprise Linux 6.2
1.1.4. New and Changed Features for Red Hat Enterprise Linux 6.3
1.1.5. New and Changed Features for Red Hat Enterprise Linux 6.4
1.1.6. New and Changed Features for Red Hat Enterprise Linux 6.5
1.2. Overview of DM-Multipath
1.3. Storage Array Support
1.4. DM-Multipath Components
1.5. DM-Multipath Setup Overview
2. Multipath Devices
2.1. Multipath Device Identifiers
2.2. Consistent Multipath Device Names in a Cluster
2.3. Multipath Device Attributes
2.4. Multipath Devices in Logical Volumes
3. Setting Up DM-Multipath
3.1. Setting Up DM-Multipath
3.2. Ignoring Local Disks when Generating Multipath Devices
3.3. Configuring Storage Devices
3.4. Setting Up Multipathing in the initramfs File System
4. The DM-Multipath Configuration File
4.1. Configuration File Overview
4.2. Configuration File Blacklist
4.2.1. Blacklisting by WWID
4.2.2. Blacklisting By Device Name
4.2.3. Blacklisting By Device Type
4.2.4. Blacklist Exceptions
4.3. Configuration File Defaults
4.4. Multipaths Device Configuration Attributes
4.5. Configuration File Devices
5. DM-Multipath Administration and Troubleshooting
5.1. Resizing an Online Multipath Device
5.2. Moving root File Systems from a Single Path Device to a Multipath Device
5.3. Moving swap File Systems from a Single Path Device to a Multipath Device
5.4. The Multipath Daemon
5.5. Issues with Large Number of LUNs
5.6. Issues with queue_if_no_path feature
5.7. Multipath Command Output
5.8. Multipath Queries with multipath Command
5.9. Multipath Command Options
5.10. Determining Device Mapper Entries with the dmsetup Command
5.11. Troubleshooting with the multipathd Interactive Console
A. Revision History