How Can I Automatically Block Users Who Send Spam?

VPS or dedicated server can be used simultaneously by several users. If at the same time one of the users sends spam, other users of the server may be blocked or included in the blacklists.

In the ISPmanager 5 Business control panel, you can configure for each user the maximum number of letters that can be sent per hour.

In ISPmanager 5 Lite and VestaCP, the limit on the number of letters can be set in the Exim mail server configuration file. To do this, use the directive:

acl_not_smtp = acl_not_smtp




begin acl




        acl_not_smtp:

                deny message = Sender rate overlimit - $sender_rate / $sender_rate_period

                ratelimit = 100 / 1h / leaky

                accept




        acl_check_rcpt:

                deny message = Sender rate SMTP overlimit - $sender_rate / $sender_rate_period

                ratelimit = 200 / 1h / leaky




                accept  hosts = net-lsearch;/etc/exim/whitelist

As a result of the execution of this directive, a limit is set for sending 200 letters per hour via SMTP and 100 letters per hour not via SMTP. How does SMTP server work?

In the file /etc/exim/whitelist, you can create a list of hosts that are not subject to the restriction.