Local DNS, first mx remote and second mx local

[Tagor]

Hi,

I have a server 1 running DNS and secondary MX. Server 2 runs the first MX. I added two MX records to my DNS (MX 10 ip.ad.re.ss / MX 20 ip.ad.re.ss).

If server 2 goes down all mail stays in the queue for some time. But I would like server 1 to deliver the mail locally if server 2 goes down.

I put the domains in /etc/secondaymx and /etc/remotedomains.

Any idea how to fix this?

[/bin/bash.org]

Currently, your mail is held up because the MTA must try the next highest MX. To short circuit this behaviour, you need to set some kind of transport map on the server. Ie. "When I get email for <somedomain.foo> I should deliver it directly to <some server>, bypassing the default mechanism." You'd need to do this for all domains that this needs to happen for. This way, you can still use your MX records to control where email comes into your network (ie. server 1 & 2 may be in different locations from each other), but you can still deliver the mail once you have it regardless of the state of the other mail servers (ie. you get fault tolerance).

Sorry, I don't know how to do this in exim as I use a pair of postfix servers as my mail gateways. In postfix you'd add something like "foobar.com smtp:[ip.of.cpanel.box]" to /etc/postfix/transports.