The receiving mailserver can do reverse DNS perfectly - just doesn't seem
to want to do it during qmail smtp connections. I checked the
/etc/nsswitch.conf file and changed it from:
hosts: files mdns4_minimal [NOTFOUND=return] dns
to:
hosts: dns files
That didn't seem to help either. Do you think a reboot or a service restart
is necessary after making this change?
At 11:49 PM 12/29/2008, you wrote:
Jeff Koch wrote:
Hi:
Does anyone happen to know why all emails received by qmail are reported
as 'Received: from unknown' even though the sending mailserver clearly
identifies itself and has reverve DNS setup?
Here's a good example from an email I just recieved:
Received: from unknown (HELO lists.sourceforge.net) (216.34.181.88)
That suggests the reverse dns lookups are failing on that server. Have you
tried some lookups manually to see if they are working? I had an issue
similar to this just recently with a new server and it took a while to
realise that I had made a mistake in the nssswitch.conf file and it was
trying to resolve everything via ldap instead of via dns.
Shane
Best Regards,
Jeff Koch, Intersessions
