Displaying 1 result from an estimated 1 matches for "m9ed0yf5002021".
2008 Oct 14
3
Sendmail and pmtu discovery
...services in charge of their firewall policy
(http://en.wikipedia.org/wiki/List_of_minor_characters_in_Dilbert#Mordac).
My mail logs are showing that customers who specifically disallow ICMP
traffic have many "Connection Reset" entries in our logs:
Oct 14 08:00:50 mailsrv sendmail[2024]: m9ED0Yf5002021:
to=<customername at customer.org>, delay=00:00:16, xdelay=00:00:16,
mailer=esmtp, pri=42476, relay=mail.customer.org. [XX.XX.XX.XX],
dsn=4.0.0, stat=Deferred: Connection reset by mail.customer.org.
I have disabled pmtu discovery on our routers as well as on all our
outbound mail servers. I...