DGoranson
2012-12-13 17:19:06 UTC
I'm having a strange issue and I thought I'd post it here in case anyone else may be seeing the same thing. I'm running postfix 2.6.6 on Centos 6.0. I've set postfix up as a relay box inside the network and NAT'd the address so that incoming mail hits the linux system. This then relays to an M$ Exchange 2010.
When the SMTP session starts between the systems, the Centos system does an RSET after the SYN and ACK. When I move the Linux system out of the network and on to a different circuit,(in a DMZ zone) and then forward the SMTP traffic to the Exchange system inside the network, the problem goes away.
I don't believe it has to do with a specific build of Postfix, as I've built 3 different systems on different pieces of Server hardware, but the issue is exactly the same. I've even compiled Postfix 2.9 on one version I built and I see the same issue as the relay starts.
I've called Microsoft and paid the $300.00, but as I suspected, they blamed the Linux system and told me it couldn't possibly be the Exchange box.
Anyone see this before?
When the SMTP session starts between the systems, the Centos system does an RSET after the SYN and ACK. When I move the Linux system out of the network and on to a different circuit,(in a DMZ zone) and then forward the SMTP traffic to the Exchange system inside the network, the problem goes away.
I don't believe it has to do with a specific build of Postfix, as I've built 3 different systems on different pieces of Server hardware, but the issue is exactly the same. I've even compiled Postfix 2.9 on one version I built and I see the same issue as the relay starts.
I've called Microsoft and paid the $300.00, but as I suspected, they blamed the Linux system and told me it couldn't possibly be the Exchange box.
Anyone see this before?