ADSM-L

Re: TSM SERVER MIGRATION from STK ACSLS tape library to IBM 3584

2006-03-28 09:57:04
Subject: Re: TSM SERVER MIGRATION from STK ACSLS tape library to IBM 3584
From: "Allen S. Rout" <asr AT UFL DOT EDU>
To: ADSM-L AT VM.MARIST DOT EDU
Date: Tue, 28 Mar 2006 09:48:35 -0500
>> On Tue, 28 Mar 2006 11:32:19 +1000, Steven Harris <steve AT STEVENHARRIS DOT 
>> INFO> said:

> Here is one way to do a gradual migration.

Superb advice.  I'd suggest one embellishment:

Set up the new primary stgpools, and the new-primary->new-copy
housekeeping at the outset (step 2) .  Then, set the old-primary
stgpools to have RECLAIMSTGPOOLS of the corresponding new-primary.

This takes one usually very heavy use of tape drives, and contributes
its' efforts to the migration.  It introduces the possibility that
something might get written to old-primary, and then reclaimed to
new-primary before it gets copied to old-copy, but that doesn't seem
particularly likely, and the data in new-primary -will- get copied to
new-copy.




> 1. Set up your new library and devclasses to use it.

> 2. set up a new set of copypools parallel to your old set of copypools, and
> run backup stg commands on all your primary pools until the copypools on the
> new library are up to date - this may take weeks, depending on how much data
> is to be copied, but can be stopped and restarted as necessary. Change
> housekeeping to copy new data to both new and old copypools. If you are
> using 5.3 parallel processing commands watch for the limit of 16 parallel
> commands at once.

> 3. Once the copypools are caught up, you can change your housekeeping to
> stop copying data to the old copypools.

> 4. create a new set of primary pools to parallel your old setup.  Change
> your diskpools to migrate to the new primary pools.  Change your
> managementclasses that go straight to tape to point to the new primary
> pools.  Change your housekeeping to backup the new primary pools to the new
> copypools.

> 5. Make the nextstg of each of the old primary pools to be its new
> equivalent.  Run migration on the old pools to move the data off to the new
> pools. The new migrate stg command with a duration will drip feed this over
> time.

> 6. Finally, when everything is copied, run del vol on each of the old
> copypool volumes (discardd=yes will be needed) and any old primary pool
> volumes (discardd=no) that need it, and clean up old definitions.



- Allen S. Rout