I had been handling $random@stonehenge.com by letting postfix deliver to my procmailrc, which fired up a separate Perl invocation to sort and deliver the mail for each incoming email. And test for spam.

The problem is the MIRVs. A lot of mail gets addressed to thereto@stonehenge, barney@stonehenge, merlyn@stonehenge, for about 10 addresses in one payload. And this type of spam seems to have greatly increased in the past few months. A burst would come in, and for the next two minutes, I was splitting and forking and Mail::SpamAssassin-ing, and loadav would hit 3 or so, and my sublease customers were complaining.

So yesterday, I bit the bullet, and learned about Amavisd, a preforking Perl daemon built around Net::Server, that could pull in SpamAssassin and some virus checkers. I carefully read the "README.postfix" file included in the distro, and set up everything.

Wow, what a difference. Now my postfix/amavisd MTA checks for spam once for the MIRVs, without forking, instead of 10 times with a lot of forking going on. My loadav has never exceeded 0.9! Hooray. Success.

I'm getting about 1 MIRV a minute. Ouch.

My only concern is that the amavisd is started and stopped outside the normal postfix engine, so I'm concerned about what happens when it goes down. (Postfix will just stop, but I won't be around to notice.) I'm thinking of a cronjob entry to just keep restarting it every half hour or so, just in case it fries.

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to Spam Fighting moved from MUA to MTA - success! by merlyn

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