Scott,

you hit the bullseye - the main problem would be volumes. But not only
ones used by single (deleted) node. The ones used by two nodes might be
bigger problem. Let say volume CBA321 hold the data for both nodeA and
nodeB, who will be the owner of the libvolume? Collocation is the key - so
you met an important prerequisite :)
Later you should not have problems - once libvolume (note!) is updated to
be owned by server-B, server-A ought not to change its status to scratch
even if is library manager. On filespace deletion data will dismiss from
*volume* and it would be deleted from the pool. But libvolume will be
owned by other server (which knows there is data) and the status would not
change.
Of course you can set maxscratch=0 on pools as insurance but this would
affect normal operations (if your server is so big to force splitting it
would not stay idle for long and "filling" tapes quickly will become
"full" ,-) and will not give too much additional security.
Also I would add a step "0.9 ) Update all volumes to read-only." and move
step 7 before step 4 to minimize disruption of service to nodes associated
with server-B.

Zlatko Krastev
IT Consultant




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Subject:        Server partitioning using TSM library sharing

Hello fellow TSMers,

We have a fairly large TSM server that we are planning to partition into 2
servers. In other words, add a second server and split the client nodes
across the two.

The hardware environment is two AIX TSM servers, both fibre attached to a
10 drive 3494 ATL.

What I am proposing to do (and looking for input) is as follows:

1) Restore a copy of TSM server-A's database to the new TSM server-B
2) Reconfigure the library and drive configuration on TSM server-B to be a
library client to the shared library manager server-A.
3) Identify the nodes that are to be associated with each server.
4) Identify the volumes associated with the nodes for each server (Storage
pools are currently fully collocated by node).
5) Run update libvol to change the owner on the appropriate tapes to be
owned by server-B.
6) Delete the filespace and node definitions for the nodes NOT associated
with each server.
7) Reconfigure half the nodes to point to the new server-B.
8) Pat myself on the back and take the rest of the day off :-)

It seems too simple....  Has anyone done this before? (hard to type with
my
fingers crossed)

The big question of course is: what happens to volume ABC123 on server-A
when the filespaces are deleted and the volume empties, gets deleted from
the storage pool, and returned to scratch? Server-B still thinks there is
data on that tape and this proposed solution would only work if he was
allowed to request a mount and read that volume.

Any and all feedback is appreciated!

Scott
Scott McCambly
AIX/NetView/ADSM Specialist - Unopsys Inc.  Ottawa, Ontario, Canada
(613)799-9269