Messaging Gateway

Hi everyone,

I have last version of SMG 10.6.2.-7. Two SMG scanners and one CC, all of them on separate virtual machines.

Two months ago, messages began to stuck in delivery queue, but not for all domains. Error for stucked messages - "450 4.4.1 [internal] Connection Timed Out".

I turned off reverse DNS lookup on both scanners, turned off DNS validation global, checked related posts from this forum and did proposed steps, but problem still exist.

I investigated "stucked mail domains" and I noticed that "SMTP transaction time" on these domains is over 15 seconds.

Does anybody know is this related to this problem and how to resolve this issue at all?

According to this problem, is it possible to configure "SMTP transaction time" somewhere in SMG, or maybe on the firewall ? 

SMG is behing the firewall (Checkpoint).

The setting for SMG's timeouts is under Administration > Configuration > host > SMTP > Delivery > Advanced Settings.The default is 30 seconds.

Are "SMG Connection Timeout" and "SMTP Transaction Time" the same things ?

I already checked this parameter above "Connection Timeout" on my SMG and value is "30 seconds"

Then it sounds like those mail servers are simply not responding, or your firewall is blocking the attempts for some reason.

WHere I can find best practices for SMG and CheckPoint ?