[afnog] Two mail servers in the same domain

[Stephane Bortzmeyer]

On Mon, Dec 15, 2008 at 09:22:24AM +0100,
 Dewole Ajao <dewole.ajao at tinitop.com.ng> wrote 
 a message of 92 lines which said:

> I'm not sure I'm reading this right but I guess what he wants is to
> have a backup of user mailboxes at any time if his primary
> mailserver crashes.

OK, in that case, it is a legitimate concern but then, it has nothing
to do with MX. 

And it is not easy to achieve since the users and the MTA modify the
mailboxes all the time.

I would suggest to just set up the spare email server and push
modification with rsync as often as possible. If the master crashes,
switch manually to the spare. Not high-tech, requires manual action,
but simple and robust.

> Ideally however, I think both servers should use the same NFS
> storage which can then be backed up somewhere else periodically.

OK, but be careful, some mailbox formats (like mbox) do not like NFS.