New mail server setup

Steve Bertrand steve at
Wed Sep 16 14:08:58 UTC 2009

Matthew Seaman wrote:
> Steve Bertrand wrote:

>> If anyone has a setup that has redundancy for their IMAP/POP services,
>> and a method to keep the changing data relatively up-to-date, I'd love
>> to hear about it.
> Now, that is a different kettle of fish.  This is a job for cyrus imap.
> I suggest googling for 'cyrus murder' -- this is almost, but not quite,
> a fully resilient mail store / IMAP system.  Your mail store is divided
> into frontend IMAP protocol servers which handle user auth etc. and back-end
> mail stores.  The protocol layer servers are fully resilient and you can
> fail over a user session at will, but the mailstores don't quite get there:
> mail is replicated across different stores, but actions modifying the mail
> store are not transactional across all the mail stores. Or in other words,
> you can lose a small amount of data if one of the mail stores goes bang at
> precisely the wrong moment.  Even so, it will do better at keeping multiple
> copies of a mailstore in synch than any locally scripted rsync setup.

This is *EXACTLY* what I was looking for!

The possibility of loosing an extremely small amount of data far
outweighs the possibility of a multi-hour outage where 3,000 users are
receiving "can't reach the POP3 server" errors.

Besides, our incoming SMTP gateway boxes cache all incoming email for 24
hours, and we can re-deliver any message to the back-end we wish during
that window.

I really try my best to design/implement all the systems I can like our
networks... multiple paths and extremely quick convergence. Being able
to take a box down to test/perform an upgrade, or during a failure
without client impact is well worth any initial large learning curve imho.


-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/x-pkcs7-signature
Size: 3233 bytes
Desc: S/MIME Cryptographic Signature
Url :

More information about the freebsd-questions mailing list