When our array went down, we were able to simply start TSM.  It came up with 
half of the mirrors off-line and ran fine.  We did not do anything special.
I do not know were it is documented.

Andy Huebner

 -----Original Message-----
From:   ADSM: Dist Stor Manager [mailto:ADSM-L AT VM.MARIST DOT EDU]  On Behalf 
Of Allen S. Rout
Sent:   Friday, May 20, 2005 8:35 AM
To:     ADSM-L AT VM.MARIST DOT EDU
Subject:        Re: [ADSM-L] Regarding TSM db and log mirroring

==> On Thu, 19 May 2005 08:38:38 -0400, Richard Sims <rbs AT BU DOT EDU> said:


> Recovery is documented in the Admin Guide topic "Restoring Your
> Server Using Mirrored Volumes".


I've been unable to find docs on starting a server on only one half of a
mirror.  Anybody ever done this?

For most of the operations which begin with "Take another backup of your
database", I've often wanted to replace that with "Break the mirror, and work
with one half of it".   You could do that indefinitely, so long as between
botched operations you re-mirror the volumes.

The obvious path (halt the server, edit the .dsk file) seems to have no
effect:  evidently the list of volumes is squirreled away somewhere else too.
You get a happy running server with all mirrors present and accounted for.


- Allen S. Rout