Re: [exim] Multiple Mail Servers

Top Page
Delete this message
Reply to this message
Author: Dave Evans
Date:  
To: exim-users
Subject: Re: [exim] Multiple Mail Servers
On Thu, Dec 27, 2007 at 02:23:20PM -0000, matt@??? wrote:
> I am currently trying to setup multiple mail servers so should the smtp
> server go down, we will receive mail to our of our other smtp servers,
> then when the original server comes back, the mail is passed on there.


If all you're trying to achieve is having one "master" mail server, where all
mail ultimately ends up, and which runs a POP3/IMAP server; and where there
are possibly some backup mail servers, but which don't run POP/IMAP, then yes,
that's nice and straightforward.

The master server runs exim, delivers to maildir (or whatever you wish), and
runs your POP/IMAP software. The backup servers run exim, and if they accept
any mail, they queue it, and try to send it on to the master server via SMTP.

> Could i replicate the sql database to another server, eg, my secondary
> mail server


Maybe; consult your database system's documentation.

Whatever method you pick, you'll need to ensure that the backup servers have
access to enough data to control the mail receiving process. For example, if
your master server's exim config uses check_local_user, you'll need to either
change that on the backups, or sync the list of local users to the backups
too.

> and also replicate the files in /var/spool/mail using unison
> once every 30 minutes (it will only replicate if files have changed).


I'm assuming that you /don't/ require POP/IMAP access on the backup servers,
so this question is redundant.

On the other hand if you're trying to provide resiliency for your POP/IMAP
access too, then that's a different question altogether, and most of what I
said above will be wrong.

--
Dave Evans
http://djce.org.uk/
http://djce.org.uk/pgpkey