What's the best possible email failover solution

[Bill Moran]

Hey,

I know questions like this get asked a lot, but I'm going to be really specific.

I know how to set up failover with a backup MX.  That's not what I'm looking
for.  We have a cyrus-imap server with lots of users connecting via IMAP,
while everything gets backed up, this only happens once a night.  Thus, if the
server were to go up in smoke right before the backup occurred, we'd lose
something like 23 hours worth of emails.

Does anyone have a solution to provide real-time mirroring of IMAP folders?
I don't mind manual intervention to get the thing running again, I just want
to ensure that if an email is received, it's on both machines and can't get
lost.  Is there a way to get real-time replication of cyrus (I'm no cyrus
guru, another fellow set this up)

I'm not tied to Cyrus either, if there's another solution, I'd be happy to
implement it.

I have an idea ... by using Dovecot with PostgreSQL storing the actual mail
folders, with Slony installed to provide real-time replication of the Postgres
database ... I don't know if Dovecot is able to store the actual mail folders
in Postgres yet, though ... Anyone?

-- 
Bill Moran
Potential Technologies
http://www.potentialtech.com