If, for some reason, the pdisk and hdisk numbering of SSA disks is not sequential anymore, then there's a way to bring order in to chaos. Usually, the pdisk and hdisk numbering order are screwed up when you replace multiple disks together. Especially on HACMP clusters, a correct numbering of pdisks and hdisks on all nodes of the cluster, comes in handy.

Unmount all file systems on the specific disks, then varyoff the volume group:

# /usr/lib/methods/cfgssar -l ssar

If this doesn't help (it sometimes will), then renumber the disks manually:

Write down the pdisk names, hdisk names, location of the disks in the SSA drawer and the connection ID's of the disks. You can use lsdev -Cc pdisk to show you all the pdisks and the drawer and location codes. Use lsdev -Clpdiskx -Fconnwhere to show the connection ID of a pdisk. Then, figure out, how you want all disks numbered.

Remove the pdisks and hdisks with the rmdev -dl command.
Create the pdisks again:

# mkdev -p ssar -t scsd -c pdisk -s ssar -w [connection-ID] -l pdisk1

Create the hdisks again:

# mkdev -p ssar -t hdisk -c disk -s ssar -w [connection-ID] -l hdisk3

Test with:

# ssaxlate -l pdisk1

if it shows hdisk3 (Usually the hdisk number is 2 higher than the pdisk number if you use 2 SCSI disks in the rootvg).

If you've done all disks this way, check with lsdev -Cc pdisk. If you're happy, then varyon the volume group again and mount all filesystems.



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