Is your ISP blocking outgoing port 25?

Randy Bush randy at
Fri Jun 19 11:53:03 UTC 2009

> We just open port 2525 for customers from ISP's blocking official SMTP
> ports so they can use their dedicated servers/domain mailservers.

for personal use, i have a box that has sshd running on 443 and i tunnel
2525 through it.  that worked even in the narita red rug when they were
at their blocking worst.

for customer use, i would push them to 465, 587 if less clued.


More information about the NANOG mailing list