Scanning and Re-Scanning

Mailing List Subscriber lists at ListOwners.Net
Tue Aug 31 04:44:39 IST 2004

I run a mailing list service (majordomo/mailman/etc) for a bunch of opt-in
discussion lists (pet lovers, knitting fans, etc).  I use the current release
of MailScanner along with ClamAV and Sophos and they work perfectly.
MailScanner is the BEST utility I've ever seen.  Thank you Julian.

I do have an issue, tho, and I'm not sure how to fix it.

When messages come into the server for a particular list, MailScanner picks
it up, scans it, and hands it off to the next alias which is usually
majordomo.   Majordomo then processes the mail and hands it off to a batcher
called TLB which handles the envelope batching a little more efficiently.  It
will group the new outbound messages into envelopes of no more than ten
recepients, and will batch them by domains.  So one message to 10,
one message to 10, and so on.  So far so good.

But when these messages are handed back to sendmail for delivery going out of
the server, they are placed back into and scanned by MailScanner.
This is a redundant action as the inbound message was already scanned by
MailScanner and found to be clean.  One already scanned message then becomes
50 or 200 messages to be scanned again.

TLB has in it's configuration the ability for me to define the mailer host
and SMTP port.  It's currently defined as port 25.  I don't pretend to fully
understand how MailScanner works, but I'm guessing that anything that comes
in on port 25 is queued to and processed by MailScanner.

Do I need to configure in another daemon to listen on another
port just for outbound emails and teach TLB to send to that port instead?  If
so, and this is my most important part of the question, how do I add this

I currently have...

DAEMON_OPTIONS(`Port=smtp, Name=MSA, M=E')dnl

can I create another entry as

DAEMON_OPTIONS(`Port=smtp, Name=MSA, M=E')dnl
DAEMON_OPTIONS(`Port=26,   Name=MSA1, M=E')dnl

and tell TLB to deliver to port 26 in order to avoid a second scan by
MailScanner?  Or am I totally misunderstanding something.

My sendmail version is 8.11.6 but I am NOT a sendmail guru.

Thanks for any suggestions.

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