DNS - Postfix

[Chuck Swiger]

On Sep 21, 2006, at 4:22 PM, Dave Kingsley wrote:
> Our DNS server coughed a major hairball and our
> postfix based email setup suddenly stopped working.
[ ... ]
> Our problem seemd to be centered around MX records.?!
>
> What do I need to post (file chuncks, etc.) to aid getting help?

The mailserver must have access to the DNS, or it will need to  
forward all email to a mail relay which does have working DNS.  It is  
likely that if you add the IP address of a working nameserver to /etc/ 
resolv.conf on your mailserver, it will become happy again until you  
can fix your own DNS.

Otherwise, you can change the "relayhost" setting /usr/local/etc/ 
postfix/main.cf:

# In the case of SMTP, specify a domain, host, host:port, [host]:port,
# [address] or [address]:port; the form [host] turns off MX lookups.
#
# If you're connected via UUCP, see also the default_transport  
parameter.
#
#relayhost = $mydomain
#relayhost = [gateway.my.domain]
#relayhost = [mailserver.isp.tld]

Uncomment the last and replace the stuff within the square brackets  
with the IP address of your ISP's mailserver...

-- 
-Chuck