Comments on: Hardening Sendmail against DDoS

By: kiranjith

kiranjith — Mon, 15 Feb 2010 08:25:02 +0000

simple and well explained..
really appreciable..

this post helped me a lot

thanks a lot :o)
//kiran

By: joe

joe — Fri, 05 Feb 2010 22:09:40 +0000

If you need your clamav installation to perform better, try put the scanning in a ramdisk filesystem.

By: mjoellnir

mjoellnir — Fri, 09 Oct 2009 10:44:35 +0000

Hello Juan,

yes, indeed, you should run clamd and tell MailScanner to communicate through unix- or tcp-sockets with clamd. Using ClamAV like you do would mean several instances of ClamAV with each loading the complete database. That is quite resource-consuming, and slow as well. If instead there is clamd running, and MailScanner (or as in my case, clamav-milter), this problem will gone immediately.
I would generally advise the usage of clamd for every mailserver (using ClamAV), by the way, no matter how many mails are processed per day. It’s the more efficient way of handling these things.

By: Juan

Juan — Fri, 09 Oct 2009 08:25:17 +0000

Thanks for this article.

But in my case, the main hungry proccess is the antivir (ClamAv). Running “top” command, and ordering by CPU usage, I can realise that ClamAv is the main “problem”.

I use today’s latest version (ClamAV 0.95.2), with the lastest version of MailScanner.

Our server process 25K mails per day, and 98% are Spam. The load average of the server is bettwen 1 - 2.5. Do you know how to reduce this high load average ?

I think it could be enhaced, running clamav as a daemon (clamd), instead of a process on the fly.

What do you think ?

By: Ria

Ria — Tue, 29 Sep 2009 12:58:15 +0000

I recently came across your blog and have been reading along. I thought I would leave my first comment. I was searching regarding mail servers and landed here. I don’t know what to say except that I have enjoyed reading. This blog is very informative . Thanks for the post.