Joe,
        If it comes down to using ADSM or AIX to mirror the database, I'd use
ADSM mirroring.  I think the big advantage to using ADSM mirroring is in
the event of the system crashing during a DB write and causing DB
corruption.  With AIX mirroring, I think you're SOL but with ADSM
mirroring, if the write didn't complete to both copies of the DB, you
stand a chance of one copy of the database not being corrupted.
Regarding RAID, I had posted questions to the ADSM-L listserver a couple
of years ago about this and received some very helpful information -
somebody had even done some benchmarking (7137 array vs. SCSI vs. SSA or
something like that - this was a long time ago - at the time, the 7137
outperformed the other options ).  We decided on using a dedicated
7137-514 disk array configured for RAID-5 w/hot spare for our ADSM DB
(16 GB) and have been very happy with the performance.  There had also
been some posts about using mirroring/striping with SSA disks but I
don't know what the results of that were.  I keep the recovery logs on
separate dedicated SSA disks and use ADSM mirroring to mirror them.

Tim Pittson


>-----Original Message-----
>From:  Joe Morris [SMTP:morris AT UNC DOT EDU]
>Sent:  Monday, January 05, 1998 10:49 AM
>To:    ADSM-L AT VM.MARIST DOT EDU
>Subject:       ADSM mirroring vs. AIX mirroring
>
>I've been browsing through the ADSM archives at Marist and could not find
>what I was looking for.  Setting up a new server that has ample space to
>replace our old ADSM server.
>
>What are the pros and cons of using ADSM and AIX to mirror the database
>and log volumes.  Mainly focusing on differences between using AIX
>mirroring and the built-in mirroring in ADSM.
>
>I had considered a RAID configuration, but it seems like that is not such
>a hot solution for the database for performance reasons.  Am I wrong?
>
>_______________________________________________________________
>Joe Morris  -  morris AT unc DOT edu  -  http://sunsite.unc.edu/morris
>Academic Technology and Networks, Development and Eval Services
>University of North Carolina at Chapel Hill      PGP by request