Setting up MailShell Anti Spam
Document #:10385
Applies To:
Synopsis:
This document details how to setup the MailShell Anti Spam filter on your MailSite server.
More Information:
To run the MailShell Anti Spam filter, you must ensure you are licensed for it. Please contact your sales representative or email
sales@mailsite.com for more information on licensing.
Once you have entered your license key into the MailSite Console, you will be able to access the MailShell Anti Spam filter option.
Server > Filtering > MailShell Anti Spam Filter.
Check the following are enabled:
- Enable Spam Scanning on this server
- Enable Automatic updates via FTP
Under the 'What to process' your selection will depend upon your license. If, for example, you have 100 mailboxes in MailSite and your license permits 50 Anti Spam enabled mailboxes, then you will only be able to select 'process all messages sent by or to scan enabled domains/mailboxes'.
If your license permits 100 Anti Spam enabled mailboxes then you can utilize the 'Process all messages received by SMTP'.
You MUST utilize the sieve filters in conjunction with the Anti Spam engine. The Anti Spam engine will assign a spam score to a message (if licensed), the Sieve Filters will then decide how to handle that message. The Anti Spam engine will tag a given message with a spam score between 1 and 10. 1 is not spam, 10 is definitely spam. A score of 0 indicates the message was not scanned. This can be due to a size limitation or licensing restriction. The score is stored within the message stream and the sieve filters will look here when processing messages. You can create rules to expose the spam score of the message in the subject header if you wish.
Process all messages received by SMTP
If you have this option enabled, then you can put your sieve filters under any category (i.e Server Receive Scripts, Domain Scripts, Mailbox scripts).
It is recommended you create a rule to reject messages with a spam score of 9 and above under the Server Receive Scripts. When rejecting messages it is recommended to provide a helpful rejection message which can assist in troubleshooting should someone report a rejection.
In addition create a rule under the Mailbox Delivery Scripts to send any messages with spam score of 7 and above to the Junk Mail folder.
Under the MailShell Anti Spam filter > Filter Configuration you can set how frequently the 'Junk Mail' folder should be purged (in days).
These scores can be adjusted to suit your environment.
Process all messages sent by or to scan enabled mailboxes
If you have this option enabled, then you CANNOT use the 'Server Receive Scripts' for any filters related to the Spam score. You must define your rules either within the Domain Filters, or Mailbox Filter Scripts.
In this case you have a Anti Spam license smaller than actual number of mailboxes on the system. Therefore MailSite needs to check on whether a given mailbox/domain has spam enabled before running a sieve filter rule. Any spam rules defined in the 'Server Receive scripts' will not run.
If you are running the Anti Spam on a per mailbox basis, then you must use any of the Mailbox level filtering. If you are running the Anti Spam on a per domain basis, you must use the Domain level filters or the Mailbox level filters.
In MailSite 7 and later, you can use the Whitelisting and Blacklisting in conjunction with the Anti Spam engine. See KB 10383
Related:
See these other knowledge base documents:
Last revised 2012-4-16