Link to home
Start Free TrialLog in
Avatar of ojgarciah

asked on

Anti-spam using exchange server 2003

Hello fellas

I have implemented Exchange Server 2003 in cluster configuration. All outgoing and incoming email is sent through an anti spam Server which does all the filtering. How ever, this server is being hammered and is becoming overload. I’d like to implement a second anti-spam server and I’d like to do some load balance. What I mean is that I want exchange virtual server to send mail trough anti-spam1 and anti-spam2, and in case any of the filters goes down, the other server can take the entire load.

If you have any suggest to do that, I’d appreciate it.

Thanks in advanced
Avatar of Wonko_the_Sane
Flag of United States of America image

I don't really know the background of the configuration, but do you really need the anti-spam boxes for outbound e-mail? If Exchange sends out the e-mail directly, you reduce the workload on these boxes, it's more reliable, easier to setup and monitor.

To use both anti-spam boxes inbound isn't a big deal. Just define a second MX record for the new server.

Is there a way to cluster the anti-spam boxes  (network load balancing)? If this is possibly it's probably not a bad way to go.

Avatar of Sembee
Flag of United Kingdom of Great Britain and Northern Ireland image

Link to home
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Start Free Trial
Simon, just an idea, I'm not really sure here: If he created an additional virtual SMTP server on Exchange, and an additional outbound SMTP connector using the new virtual server, but with the same cost and address space as his normal outbound connector... then use GW1 as smarthost on the first connector, and GW2 as smarthost on the new connector... Would this load-balance?

It would still work fine if one of the boxes went down, but I'm not sure if it does load-balancing.
Exchange can't load balance or failover outbound traffic.

Thats it.
Nothing you can do about it.

You can configure as many SMTP Connectors, virtual servers or whatever that you like, Exchange will use the first one that it has permissions to use.

To be quite honest, I don't really see the point in doing it anyway.

Back to the question: You could also use your first server as primary inbound gateway and the second one as primary outbound gateway - this way the workload is at least not on one box only. But if you want them to be redundant tone single server needs to be able to handle the full load anyway...
Smebee's method is the only method
because Exchange will Round roubin between servers in the SMTP Connectore, When exchange find's multipe Bridgheads or Smart hosts server he will load them by using Round robin this is by design, check the routing toplogy guide for exchange 2003
the other way is to put the spam servers behind NLB but i have never did that
Avatar of ojgarciah


Thanks a lot

I though I could also use CNAME in DNS server for two hosts (one for each filter server) and set only one SMTP connector in Exchange, so each time a consult is made, it will alternate the IP address each time routing the traffic between both servers.

For inbound it is not really a problem, all I have to do is add a MX record.
As the result of the DNS query is cached I'd rather use the round robin method Sembee described.