At 9:27 AM -0400 10/22/02, Lawrence Clark said:

Even though there may be a slight performance hit on writes, I've placed
the TSM DB on RAID-5 to ensure availability and no down time in case of
a disk loss.

With RAID 5, is there any point in software mirroring (dual copies of
database)?

Our DB is on RAID5 (Shark).  We also have 2 copies of it, except for
one extent that we added in a crunch when it filled up.  Are the dual
copies overkill on RAID 5?  I know that even RAID is not totally
infallible, and we could have a potential disaster that wipes out the
whole Shark.  But that's why we have backups.  The chances of that
are pretty slim, and I can't imagine any scenario where we could have
a RAID failure that wouldn't leave us so dead that we'd have to
restore anyway.
--


Matt Simpson --  OS/390 Support
219 McVey Hall  -- (859) 257-2900 x300
University Of Kentucky, Lexington, KY 40506
<mailto:msimpson AT uky DOT edu>
mainframe --   An obsolete device still used by thousands of obsolete
companies serving billions of obsolete customers and making huge obsolete
profits for their obsolete shareholders.  And this year's run twice as fast
as last year's.