RE: Replacing Disk Drives With Higher Capacity

Hi Bill

The best approach largely builds on what outage windows you have available.

I would certainly avoid if I could and unload reload.

I'd start with a plan along these lines:

- Save system
- Restart System to DST
- End mirroring
- Power down system and pull out ex-mirrored drives (24 X 8gb)
- Install drives in blank slots (24 X 17gb)
- Restart system to DST
- Add 23 X 17gb drives to ASP #1 (Leave one unconfigured for load source
copy)
- Logically remove 23 X 8gb drives
- Copy Load source drive onto remaining 17gb drive
- Power down system
- Remove 24 X 8.5 gb drives
- Relocate Load Source copy to load source slot
- Install 24 x 17gb drives
- Start Mirroring
- Save system (maybe just a 22, but capture the config with a bootable tape)

I think this could take a while, but you could easily stage it over a couple
of outages.

Your biggest issue would be to get enough 17 gb drives installed in the
first pass to avoid any disk hotspots.

The more work you do beforehand identifying and understanding where
everything is, the easier it will be.

Regards
Evan Harris

-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx
[mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of Bill
Sent: Thursday, 25 September 2008 11:00 a.m.
To: midrange-l@xxxxxxxxxxxx
Subject: Replacing Disk Drives With Higher Capacity

I've got a 730 on V5R2 with 48 mirrored 8GB drives, system is currently
at 70% utilization. I purchased 48 17GB drives with a plan for a full
scale replacement.

I'd really like to avoid a save/restore scenario, which I believe I
-could- do with save storage. What I'd rather do is a piecemeal
replacement. Anyone have any ideas or comments?

One idea I have would be to stop mirroring on the system. This should
give me immediately 24 unconfigured drives, correct? Could I then pull
the unconfigured 24 and replace them with 24 17GB's, configure them and
then start mirroring? Obviously the problem with this is mirroring is
stopped.

One other option would be to pick a few mirrored pairs and remove them
from the ASP. Replace them, add them back and then continue on. If
this is feasible, could this be done via SST, or would it need to be
done via DST? I'm thinking that it has to be via DST since mirroring is
involved.

Also, can the load source only be replaced with save/restore?
Backup/Restore manual doesn't seem to cover this.

Bill