As our old and new customers alike already know we utilize MailScanner for server side and user side SPAM control. MailScanner provides us with the best ability to have full control over what email we want to receive and what we do not want to receive.

The amount of SPAM has increased dramatically. In order to give you some insight as to how much our two main shared servers were processing on average 25000 emails a day through MailScanner. If this is not an alarming number in itself here are a few more statistics.

Out of the 25000 emails that were processed MailScanner was marking approximately 5000 as "clean" and the rest were being marked as SPAM.
There are a few bad things about this.

1. The first being SPAM that you may end up receiving.

If you have chosen to receive all the email that MailScanner marks as SPAM you are receiving a large number of emails that you do not want. (Although you do have that option to delete those before you get them through your MailScanner control panel)

2. Server Processing Used

The server utilizes a certain amount of processing power for each email that is scanned. If we can cut that number down server performance will increase as a result.

With all of this in mind we recently took the following action to reduce the amount of unwanted email traveling through our systems.

We are allowing our first stop in email processing (Exim our email server) to check to see if the sender is in a few select RBL (Real-time Blackhole List). Previously MailScanner was also checking RBL's and marking them immediately as SPAM. By having exim check before MailScanner we can solve both of the issues above. Exim immediately rejects the email before it is allowed to go any further. This is email you did not want in the first place.

This has subsequently reduced the amount of emails processed in any give day to around 12000 which is a significant drop. So out of the 25000 that were being processed roughly half were coming from known spam sources.

We believe this is the best route to go not only for minimizing the SPAM that even makes it to the end user but also to limit the resource usage on our servers.

Gustave Dahl