Alfredo Saldanha: > Dear, > > I'd like to know if is there some way to disable automatic or manually > Postfix filters in case of failure (overload) or something. > I'm asking this because I was an incident where, under an overload of > messages, I had problems with my mx performance (very high CPU load and > memory usage) to deliver messages through filters header and body checks > and also a check for a policy server. > Somewhere in an overload, some messages were blocked, and would > certainly "whitelisted" the Policy Server, but it was no longer > responding to connections due to high load on the server processes. > Then ask them, is possible turn off or divert messages from filters like > cidr (check_client_access), body (body_checks) and header checks in the > event of an overload of messages?
First of all, you must configure the system such that Postfix can handle the load for the configured SMTP server process limit. If the default process limit (100) is too high for your system, reduce the number. http://www.postfix.org/postconf.5.html#default_process_limit You can stress test Postfix performance with the smtp-source utility which is included with Postfix source code. http://www.postfix.org/smtp-source.1.html Postfix has an overload-adaptive mechanism, but you should first reduce your process limit until it is small enough that your system can handle the load. http://www.postfix.org/STRESS_README.html Wietse
