NO inspect esmtp

If your email server or email gateway is behind a Cisco ASA firewall, double-check those default inspection rules. TURN OFF ESMTP Inspection to guarantee that the firewall is not messing up your mail flow. I have seen this problem over and over again. The Cisco inspection rules silently reject some SMTP commands and re-write others just enough to make your email administrator’s life miserable.

show run | include smtp
# if you see a rule for "inspect esmtp", remove it from the config 
# check with "show run" to verify that it's gone for good!
# "write mem" to save your changes!!!!

About notesbytom

Keeping technology notes on to free up my mind to solve new problems rather than figuring out the same ones repeatedly :-).
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