Hi

Hope this question is on the correct location.

I'm interested to know how AIX handles a config change on a lun?

I’m thinking in terms of either converting from STD to R1 (or DRX) or R1-R2 personality swap or more imprtantly if using the new FAST stuff in a V-Max, a lun may start life as a RAID 1 Mirror on FC disk, then get elevated to RAID 5 on Flash, or perhaps be RAID 1 Mirror on FC then get dropped down to RAID 5 FC.

In all of the above scenarios, would we have to effectively reconfigure the ODM for the LUN(s)?

e.g.

1) stop app
2) umount file systems
3) take VGs offline
4) remove powerpath devices
5) remove native devices
6) make LUN changes
7) run cfgmgr to re-discover devices (at this point i suspect it should pickup new attributes)
8) powermt config
9) bring VGs back online.
10) re-mount file system
11) re-start my app

Since PVID should not change I assume that volume group will be able to find the devices that belong to each VG ?

Not sure how that works with FAST, if it does it all automagically.

I think the data on the lun remains intact, and the access to the lun remains the same, but the AIX host may just report it incorrectly?

thanks