Re: [Exim] Secondary Mail Server/Looping

From: "Steven R. Bourque" <sbourque@???>
> Our mail server is secondary for some domains, and it is
> relaying/accepting the mail fine for those domains.

Ok.

> As soon as it gets the mail and accepts it, it appears to check DNS for
> the MX records, and sees that the next one from the primary (which is
> down) is address 207.139.193.66 and tries to send it there. The
> firewall receives it and sends it back to 10.10.6.70, this process goes
> on until it detects the loop and the message is dropped.

So you mean your primary is down ?!?!?!
And what about when it is up, does this configuration works fine ?

This is happening (I think !!!!), because the backup server is
207.139.193.66 (which in turn, tunnels to 10.10.6.70).
You need to configure 10.10.6.70 also as an intermediate backup server for
the domains. This way, the mails will not loop anymore, since they are
already there, and will only leave to go to the primary server, whenever it
comes back up.

For example, let's assume you have this...

domain.com MX 10 primary.domain.com
domain.com MX 20 207.139.193.66

Then insert a MX entry like this:
domain.com MX 15 10.10.6.70

This should do the trick.

Have fun,
Marcelo.