Storage and backup for large IMAP servers?

[Gary Mills]

We have people who are asking for unreasonable amounts of e-mail
space.  I'd like to estimate a configuration that would supply that
amount of space, just to see what it might cost, and how it could
be managed.

Let's say we have 3000 employees, and want to give them 1 GB each.
That's 3 TB of space.  What are people using for that amount of IMAP
storage, with reasonable performance?  How do you provide backup and
restore capability for it?  Would a storage system that provides
on-line snapshots simplify the backup requirements?

-- 
-Gary Mills-    -Unix Support-    -U of M Academic Computing and Networking-
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