I have an FC9 box w/ multiple interfaces running sendmail for some simple server status messages. Recently I started receiving error messages saying "Relaying denied. IP name lookup failed". For some strange reason, sendmail is attempting to lookup the IP name on the secondary interface - not the primary interface as it should.

If I add the secondary interface IP to the /etc/mail/access file, recompile and restart sendmail, it works fine - but I think this is more of a band-aid than a solution. Can anyone shed any light on what might be happening?

...and that's where the problem starts. Fedora Core 9 is obsolete: it doesn't receive security updates, bug fixes and improvements. That may not matter much to you but it matters to the rest on the 'net.
Remember Linux may be free to use but using it is not free of responsibilities.
If you want to keep up with Fedora then install 16 (from scratch, upgrading to 10 and on makes no sense at all) and BTW 17 will soon be released. Else move to a distribution with a longer support cycle but whatever you do do it RSN.


Recently? When did this behaviour start? What chances were made to the system or the network at that time? Are there any possibly related resolver or network errors?


If it works then it works. Doesn't seem a stopgap solution to me. Just firewall new connections to TCP/25 on the interface if you shouldn't receive mail on the port.

Thank you - appreciate the feedback. I know FC9 is horribly out-dated, but I'm stuck with it for the time-being. I plan on moving to RHEL6 as soon as possible. In the meantime I'll stick w/ the solution in the access file. Thanks again!