Postfix not relaying correctly
Hello. I have the following issue:
I am using postfix to notify on certain script failures. It is running on a machine with 2 nics, each on a separate network (lan and wan). On the lan side is our exchange server which postfix relays to. When both nics are up, it relays fine. When the lan nic is taken down, postfix no longer relays correctly and starts listing something along the lines of:
relay=root<at>localhost changes depending on the user, so it looks like it is relaying local instead of using my relay.
sendmail: o5MHHU5A002690: from=user, size=205, class=0, nrcpts=1, msgid=<201006221717.o5MHHU5A002690>, relay=root<at>localhost
sendmail: o5MHHU5A002690: to=user, delay=00:00:00, mailer=esmtp, pri=30205, dsn=4.4.3, stat=queued
I can still ping and access the exchange server via telnet on the same ip and port 25 so its not a firewall issue. It looks like a routing issue but nothing has changed aside from a network card being disconnected.