On 12 Sep 2006, at 16:51, Kjetil Torgrim Homme wrote:
interesting. is one of the replicas off-site? you don't worry about
EMP or stuff like that? for how long do you keep the expunged
messages?
I think turning off tape backup would be a very tough sell around
here...
In our test runs, restoring our data (12 TB and growing) from TSM
would take 6-8 weeks. To get a reasonable restore time from our
(YMMV) TSM installation for Cyrus IMAP for disaster recovery purposes
is cost prohibitive -- more expensive that our entire IMAP
installation. It works fine for user-error, tho.
replicas are off site. We're keeping unexpunged messages for one
week, which is per University policy. Our centrally run backup
service is a rather old TSM installation. It needs to be upgraded.
The cost difference between upgrading TSM and duplicating our IMAP
infrastructure was strongly in favor of duplicating IMAP. As an
added benefit, in the event of a more-likely disaster (fire / flood /
power problem in our data center, all of which we've experienced in
the last 10 years), the duplicate IMAP installation could be
immediately put into production. Our AFS installation is also moving
to disk-only backups.
Personally, if UMich experienced a disaster involving EMP or other
TEOTWAWKI scenarios, I suspect that losing archived email would be
the least of our worries. I haven't heard that from UMich disaster
planners, tho.
:wes
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