You can do it with storage methods (SRDF), but i would do it with simple AIX means. This method will require no downtime at all, you can do everything during service time:

- Create new LUNs from the new storage equal in size to the set of disks you use now and let the "cfgmgr" run on both nodes.

- Then add the new disks to their pairwise counterparts on th active node ("extendvg") and use "mirrorvg" to set up a new mirror.

- When the disks are synced do a "importvg -L" (learning import) on the inactive node from the old disks.

- On the active node do a "unmirrorvg" and a "reducevg" to the old disks.

- On the inactive node do a "importvg -L" again, this time from the new disks. VG information is now consistent again.

- remove old disks from the configuration. Once you have them physically disconnected run "cfgmgr" again on both nodes.

Here is an example run: vg1 has 1 disk "hdisk1" (100G) from the old storage.

Create a new LUN from the new storage, which is 100G too. Run "cfgmgr" on both nodes. Say, the new disk is hdisk11.

Create the mirror: Notice that i postpone the syncing because this way i can sync several VGs at once and i can parallelize the syncing (see "-L" switch to "syncvg").

Code:

root@activenode # extendvg vg1 hdisk11
root@activenode # mirrorvg -s vg1 hdisk11
root@activenode # syncvg -P 32 -v vg1 &

Make configuration known on second node:

Code:

root@passivenode # importvg -L vg1 hdisk1

Remove original disk:

Code:

root@activenode # unmirrorvg vg1 hdisk1
root@activenode # reducevg vg1 hdisk1

Make final config known again on passive node:

Code:

root@passivenode # importvg -L vg1 hdisk1

I hope this helps.

bakunin