-----Original Message-----
UniVerse Transaction Logging will solve the problem experienced with the
proposed HW / SW solution.  ...

Being very nit picky, there is one point when a file can be corrupted...

UV Transaction Logging corrects this problem.   After system failure,
when WarmStart occurs , the open transaction log is applied against the
UV data files ensuring that the internal file structure is intact.

Thanks,
   Steve

   Stephen M. O'Neal, CDP &  IBM Certified
   SWG Services Sales Specialist / Channels & U2

P.S.  I will be speaking on the interaction of HW, SW and OS at
-------------------------

Steve,

If you'll indulge some picking of nits on my part too, you are assuming
that the WarmStart recovery is being applied to the Primary disk set.
The logs are marked Full/NeedSync with respect to the primary data
disks, not the replicated disks.

Suppose the primary disks are destroyed.  While TxLg will still be
helpful, the WarmStart recovery mechanism won't.  The replicated log
disks are not synchronized with the replicated data disks, so you have
to RollForward explicitly, and not depend on WarmStart recovery.  You'll
lose some last minute data,  but if the data center burnt down, that's
probably the least of your worries.

One caution: If the replicated log disks are not as current as the
replicated data disks you could still have corruption.  For example, at
the moment of the crash, a Split/Merge operation might be partially
replicated on the data disk,  but the corresponding entry in the
transaction log not yet replicated from the primary log disks.  TxLg
would not fix the split/merge.   Solution: On the SRDF/Veritas/etc. side
make sure that replication of the logged disks is higher priority than
data disks.  Right?  Wrong?  Comments?

Chuck Stevenson

P.S.  I look forward to your conference session.  This is the 1st time I
get to attend in about 4 years.
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