Our solution is to use a dedicated server, which acts as a mail proxy server (hereinafter postfw), for pre-filtering messages. The system uses free software: exim, mysql, memcached, spamassassin, clamav.
After passing all the checks, on the basis of collected points, the mail message is marked as spam or is rejected by postfw.
On the basis of these points our system creates the base of the sender's IP Reputation which is used by postfw. The decision to accept / reject message as well as the reputation of the sender's ip also has weight.
Extremely pernicious IPs (also based on his reputation) can be automatically blocked by firewall (iptables).
For high speed processing of mail messages, a working base reputations of Ips is stored in memcached. Periodically it is aggregated and recorded in a permanent database in mysql (used only for statistics)
Currently postfw supports cPanel servers. This is in addition to manually adding domains in the administration panel of postfw. Other hosting panels are not yet supported.
If the message is passed, then postfw determines at what server should be redirected the message (the server where the mailboxes are physically located in that domain).
Postfw filters only incoming messages. Outgoing messages do not pass through postfw, and are sent directly from the server where mailboxes of a domain are phisically placed.
For filtration, it is necessary that the MX-records of domains point to the server's ip where postfw is placed.
Our system has a control panel on php, which allows you to easily manage it without installing of additional software.
Options of panel:
- Add / Remove Domains
- View statistics on domains (accepted / blocked)
For details, please contact us on
sales@remsys.com
REMSYS offers extremely effective solution for unloading mail servers
