Re: [exim] Multiple Backup DNS

> > The problem occurs when my primary server goes out, leaving the other
> > two alive. At that point, the secondary server (mail.friend.org) gets my
> > mail and looks up the available MXes. Since mail.domain.org is not
> > available, but mail.isp.net is, mail.friend.org immediately forwards it
> > on to the tertiary server (mail.isp.net).
>
> This should not happen. What is the configuration?
>

The secondary server is set up with my domain in relay_to_domains. It will
relay to my host if my host is up, just fine. And it used to queue for my
domain before I had the ISP acting as a tertiary backup. I added them since
my friend and I are on the same access point for the same ISP, so if our
net goes down, we're both out. The relay messages seem to get sent out on
the dnslookup router, which looks like:

dnslookup:
driver = dnslookup
domains = ! +local_domains
transport = remote_smtp
ignore_target_hosts = 0.0.0.0 : 127.0.0.0/8 : [host ip]/32
no_more

So it looks like mail.friend.org is doing a DNS lookup, finding
mail.isp.net to be available, and going on its merry way. It looks like
ignore_target_hosts is an IP address list. I don't have control over the IP
of my isp's mailserver, so i'd rather stick with the domain name they have.

Thanks,
-- Justin