I am really getting frustrated with Sophos MTA. IT is a real pain in the B... when it starts failing. I have read a lot of articles tried a whole of solutions and nothing works! My MTA is only used inbound. I am not scanning mail outbound. My mail gets accepted by sophos but stays stuck in the queue with a failed notice!.
I can telnet to port 25 from the sophos to my exchange and send an email. It works fine!!
A tail of the smtpd_mail.log reveals nothing :
12 static_route_bymx_for_email router called for email@example.com domain = almapavi.ca14712 set transport remote_smtp14712 queued for remote_smtp transport: local_part = minixxxxxxx14712 domain = almapavi.ca14712 errors_to=NULL14712 domain_data=NULL localpart_data=NULL14712 routed by static_route_bymx_for_email router14712 envelope to: firstname.lastname@example.org transport: remote_smtp14712 host almapavi.ca [X.Y.4.25]14712 host almapavi.ca [X.Y.4.20]14712 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>14712 After routing:14712 Local deliveries:14712 Remote deliveries:14712 email@example.com Failed addresses:14712 Deferred addresses:14713 T: remote_smtp: firstname.lastname@example.org locking /sdisk/spool/output//db/retry.lockfile14713 locking /sdisk/spool/output//db/retry.lockfile14713 locking /sdisk/spool/output//db/wait-remote_smtp.lockfile14712 LOG: retry_defer MAIN14712 == email@example.com R=static_route_bymx_for_email T=remote_smtp defer (-53): retry time not reached for any host for 'almapavi.ca'2019-05-22 11:15:14.336  c9eZfm-j9CDMM-zO == firstname.lastname@example.org R=static_route_bymx_for_email T=remote_smtp defer (-53): retry time not reached for any host for 'almapavi.ca'14519 LOG: queue_run MAIN14519 End queue run: pid=145192019-05-22 11:15:14.336  End queue run: pid=1451931226 child 14519 ended: status=0x031226 normal exit, 031226 0 queue-runner processes now running
a tcpdump of the smtp traffic to my mail server does not reveal any errors ..
I am at a complete loss....
restarted services, rebooted my mail server... I really need help in solving this issue.
Wow, just wow !!! I fixed the issue by reducing the MSS to 1460 on the interface closest to the mail server! Bang they all came in... I have no clue why this would all of a sudden have such and impact.