[GLLUG] Email: problems with anti-virus and spam rejection

[Chris Bell]

Hello,
I have been trying to configure a pair of boxes as "hubbed host" mail server in 
the main network, and mail gateway receiving SMTP in the DMZ, both running 
Debian exim4-daemon-heavy, with spamassassin and clamav/clamsmtp on the mail 
server, but sa-exim and clamsmtp on the mail gateway. This usually results in 
a batch of delayed emails, then the gateway grinds to a halt with a shower of 
messages in /var/log/exim4/panic.log which quote access problems. I have 
followed all the instructions found about fixing access problems, and now 
suspect that the problem is caused by sa-exim rejecting (or redirecting to 
/dev/null) obviously junk emails before clamsmtp is ready. Is anyone else 
seeing this? I have not seen any problems once mail reaches the server, and am 
not bothered by a small delay while the mail is re-checked there.
A quick google search for "sa-exim and clamsmtp" has just found
https://patchwork.kernel.org/patch/10437767/
which appears to agree that there may be a race condition somewhere.
-- 
Chris Bell
Website http://chrisbell.org.uk