The one topic no one is mentioning is Disaster Recovery.  It's very hard to
collocate an offsite pool.  The only way to reduce the number of tape
mounts is to do some type of full backup periodically (either backup or
archive).

I started doing "full backups" of SAP filesystems after doing a DR with two
3590-B11's as my 3494 tape library.  After 1800 tape mounts to restore
/saparch, something had to be done.  Watching TSM restore 1 file from each
tape made it imperative.  "Full backups" was the something (Note the quotes
- see below).  Taking "full backups" periodically drastically reduces the
number of tape mounts needed to restore at a DR, since the data should not
spread across more tapes than the number of days since the last full
backup.  So our 1800 mounts above comes down to 7, if weekly fulls are
taken of the systems.

Now comes the argument of "That's duplicating a lot of data!"  Yes, it
does.  So figure out what needs to be restored in this way (the answer is
"Not all of /saparch" for you SAP accounts out there) to bring the system
back up in case of a disaster.  Work with data owners to see what they need
back immediately, and what can wait until after the system is back online
and running.  There's more in that second list than you may think!

My "Full Backups" are therefore weekly archives of critical path data,
which are kept for 2 weeks.  At a DR, I do a retrieve, then a restore of
the incremental data since the archive (then I script the retrieve and
restore, just to speed it up even more, but that's a different thread).

Nick Cassimatis
[EMAIL PROTECTED]

Today is the tomorrow of yesterday.

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