JW wrote regarding '[SLE] Look for opinions: Best Email server w/ virtual domain and anti-spam functionaliy?' on Thu, Sep 09 at 16:44:

Hello,

In the past 4 years we have tried using both Postfix and Qmail, several different virtual-domain packages, and spam assassin.

We handle many different domains for our customers so virtual domain support is an absolute requirement, this goes for the pop3 side as well as the MTA side.

Recently we have had to shut spam assassin off of our qmail server because it was running the load average so high that it was ceasing to function properly.

So what I'm looking for is opinions on what the best combination of packages is that will provide at least the following functionality without running our mid-range hardware to the ground. I'm willing to consider anything, even commercial options.

1. Virtual domain support (have to be able to email users of the same user name at many different domains, i.e. john@abc.com, john@123.com, john at def.com, etc).

2. Anti-spam software. This needs to be somethign effiecient - python and perl-based options that grind business to a halt are not good.

3. pop3 access

Other highly-desireable features that aren't absolutely required:

Some good way to provide smtp for dynamic clients - pop-before-smtp or smtp authentication - cannot be IP based.

Personally, I'd stick with postfix (or qmail). It sounds like you just need a more efficient anti-spam setup. With my postifx install, I have a bunch of regular expression header checks that block lots of stuff before it ever gets queued. That helps some. Then, I run spamd on a seperate machine (the DNS server, typically, since it's not doing much else). That takes the spam checker load off of your mail machine. You could pretty easily set up a simple round-robin spamd hostname with a couple of machines running spamd and sharing configuration stored in mysql / NFS mounts. That's kinda what I do at home. I don't have a huge email load, but a 486 machine handles all of my incoming mail (it's 5PM and I've done about 5000 messages since 9AM today) with spamd running on an old dual celeron machine. Load averages are around 0.1 or so most of the time, with the scanning taking less than 1 second for most messages. If you distribute that across a couple of machines, you could handle >120 messages/minute on this old hardware that costs almost nothing to buy... Or, find another antivirus/spam scanner. They're all gonna slow thngs down, though, so you may as well just set up multiple MTAs with their own spamd and get the redundancy + speed increase from cheap hardware. --Danny, setting up a third MTA at work tomorrow - to take some of the load

On September 9, 2004 03:43 pm, JW wrote:

Hello,

In the past 4 years we have tried using both Postfix and Qmail, several different virtual-domain packages, and spam assassin.

We handle many different domains for our customers so virtual domain support is an absolute requirement, this goes for the pop3 side as well as the MTA side.

Recently we have had to shut spam assassin off of our qmail server because it was running the load average so high that it was ceasing to function properly.

You can put SpamAssassin on a separate server, which should fix your problem. Are you using spamd/spamc? That should take care of the startup overhead, after that Perl should slow things down too bad. I don't know of a better Anti-Spam system though. Chris

Thanks

-- ---------------------------------------------------- Jonathan Wilson Cedar Creek Software http://www.cedarcreeksoftware.com