Emails are not being processed on the SMTP Prevent server.
Relevant Versions: ALL
Check the following to be sure your implementation is correctly configured and functioning. Without all of these elements in place, messages cannot transit Prevent.
Note: Please see TECH219996 to start because port 25 is typically unusable on Linux, so steps must be taken to work around that.
1) Is there a network path from the upstream MTA in question to Prevent?
2) Is Prevent listening on the expected port?
3) If the MTA is sending mail to a port below 1025 then:
a) Is the firewall service (iptables) running? If they are not running, there will be no communication with the MTA at the proper ports. Restarting the IPtables will resolve this issue.
b) Is the mapping from the port to which the MTA is sending the message to the port at which SMTP Prevent is listening (Advanced Settings>RequestProcessor.ServerSocketPort) defined
4) Is there a network path from SMTP Prevent to the downstream MTA?
5) Is the downstream MTA accepting connections on the return port (Advanced Settings>RequestProcessor.MTAResubmitPort)?