Utilities: Administration: Server: Server Settings: Automatic Maintenance: Mail Loops

Loop Detection

ListManager automatically tracks how many messages per day are sent from a foreign address to a ListManager address. If the number of messages in one day exceeds the Loop Detection threshold, ListManager cuts off the mailings, issuing a single refusal message, and then discarding the rest of the messages in that 24 hour period.

This feature is useful for automatically breaking mail loops that aren't able to be stopped through ListManager's other mechanism, and also for stopping a mail bomb attack. Say, for example, that someone sets their email program to send thousands of messages to your auto-responder, in order to mail bomb you, and tie up your server. This feature will detect this, notify the administrator and automatically stop the process.

Note: Some sites use a web CGI script to sign people up to their list. In such a case, the script might be sending from the same address every time, and to the same address every time, thus being perceived as a mail loop if the quantity of mailings goes over the loop detection threshold. In such a case, you should put an exception for that specific from/to combination to exempt your script from this logic. If you forget to do this, the server admin will receive notification of the potential loop, and you'll thus be reminded of the need for an exception.

Loop Exceptions

The Loop Detection feature in ListManager keeps track of how many messages From: one person have gone to each To: address, and sets a limit on the daily number. However, you might want to specify exceptions to this feature, which you can do using this "Loop Exception" field.

For example, if you have a script which generates many commands from the same email address each day, you can put an exception in for your script, and still retain tight control over breaking mail loops. To use this feature, specify either the to sender or the recipient address, or specify a sender/recipient email address combination by putting the "sender-recipient" together on a line, separated by a dash. You can specify as many exceptions as you like each on a separate line.

For example, to put an exception for all mail from root@mail.yourcorp.com you would enter this:

root@mail.yourcorp.com

To put an exception in for a local auto-responder named "sales@mycompany.com" you would put in:

sales@mycompany.com

And if you wanted to put an exception in for only the messages from root@mail.yourcorp.com to a local auto-responder named "sales@mycompany.com" you would put in:

root@mail.yourcorp.com-sales@mycompany.com

Note: If a loop is detected, ListManager will send the server administrator an email notification of the loop. The email notification will contain the From and To information for that message, as well as the instructions for putting an exception for that loop, if so desired.

More

1. Utilities: Administration: Server

1. Utilities: Administration: Server: Server Settings: Automatic Maintenance: Error Mail

2. Utilities: Administration: Server: Server Settings: Automatic Maintenance: Logging

3. Utilities: Administration: Server: Server Settings: Automatic Maintenance: Purging Old Data

4. Utilities: Administration: Server: Server Settings: Automatic Maintenance: Mail Loops