The Littlest Things
Wednesday, June 20, 2007, at 07:22AM
By Eric Richardson
I've been having a problem lately sending some random emails. They simply wouldn't go out. qmail would tell me:
deferral: Sorry,_I_wasn't_able_to_establish_an_SMTP_connection.
Trying to telnet to port 25 on the receiving mail host would simply time out, unable to connect. From a different host it would work perfectly.
Finally today I got fed up, prepared to think this was something I just wasn't going to solve. I was almost ready to try routing my outgoing mail through a different host when I saw something a little funny. In my routing table I had an incorrect route that was sending 66.0/8 out via eth0 with no gateway. I ran some queries and sure enough, all the hosts I couldn't connect to were 66.x.x.x.
One simple:
sudo /sbin/route del -net 66.0.0.0/8
and everything was working.