[SOLVED] 2nd external mta

[cayaraa]

We've been running zimbra in a split domain for a while with zimbra acting as the secondary system. We added another upstream mta and we tried adding it as a second "Relay MTA for external delivery" through the zimbra admin console. This updated the postfix relayhost to have two MTAs....which caused postfix to error out with the following:

Oct 25 08:51:40 zimbrahost postfix/trivial-rewrite[2409]: fatal: relayhost parameter setting must not contain multiple values: mta1.domain.com:25 mta2.domain.com:25
Oct 25 08:51:41 zimbrahost postfix/master[11747]: warning: process /opt/zimbra/postfix/libexec/trivial-rewrite pid 2409 exit status 1
Oct 25 08:51:41 zimbrahost postfix/master[11747]: warning: /opt/zimbra/postfix/libexec/trivial-rewrite: bad command startup -- throttling


Anyone know if I did something wrong or am I running into a bug?

Thanks.

[Krishopper]

You can only have one relay host specified in the settings.

You'd have to set up some time of clustering if you wanted it to balance. DNS can do round-robin (multiple A records for one hostname), but there is no automatic failover if one goes down.

[phoenix]

Try these:

Relay per Domain - Zimbra :: Wiki
[SOLVED] multiple accounts on smtp relay

[cayaraa]

Originally Posted by Krishopper

You'd have to set up some time of clustering if you wanted it to balance. DNS can do round-robin (multiple A records for one hostname), but there is no automatic failover if one goes down.

Yup we've done DNS round-robin before for other services....not the best. And in this case we aren't to concerned about load balancing but failover.

Originally Posted by phoenix

Relay per Domain - Zimbra :: Wiki
[SOLVED] multiple accounts on smtp relay

Thanks phoenix but these are mtas for the same domain so unless I'm misunderstanding that won't really work for us.



Looking through some postfix stuff regarding this error I've ran into smtp_fallback_relay. Does anyone know if this is safe to use with zimbra in a split domain setup as the secondary server?

*goes to test*


As a side note....is it then a bug in the zimbra web administrative console that adding multiple external mtas puts them all in the postfix relayhost?

[cayaraa]

Originally Posted by cayaraa

Looking through some postfix stuff regarding this error I've ran into smtp_fallback_relay. Does anyone know if this is safe to use with zimbra in a split domain setup as the secondary server?

*goes to test*

This seems to be working:
$ postconf -e fallback_relay=backupMTA.domain.com:25
$ postfix reload

in the postfix config smtp_fallback_relay = $ fallback_relay

Please note: there are warnings about not using this when using MX records for mail routing.
Postfix Configuration Parameters