How do I configure multipath in a RHEL 5 kickstart installation?

Environment

• Red Hat Enterprise Linux (RHEL) 5
• anaconda kickstart installation

Issue

• How do I install RHEL 5 to a multipath device with a kickstart?
• Need usage examples for multipath configuration in kickstart installation.
• Installation stops with a kickstart error indicating that it can't find the scsi lun when addressed from a kickstart by either /dev/disk-by-id or /dev/disk-by-path.

Resolution

• Use the mpath option at the boot: prompt to cause the installer to setup multipath maps:

boot: linux mpath ks=<URL> <other-ks-options>

• Use the multipath directive in the kickstart file to associate a multipath device name with a specific SCSI ID:

multipath --name=mpath0 --device=<SCSI ID> --rule=ignore

The SCSI ID of the device can be obtained from an installed system or rescue mode with:

# scsi_id -gus /block/sdX

where sdX is the device name.

NOTE: It's possible to use the device name which is a member of the multipath device instead of SCSI ID. Specifying the device name is a only way In Red Hat Enterprise Linux 5.4 and before.

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