Postfix project is Wietse Venema's mailer that started life as an alternative to the widely-used Sendmail program.
Postfix attempts to be fast, easy to administer, and secure, while at the same time being sendmail compatible enough to not upset existing users. Thus, the outside has a sendmail-ish flavor, but the inside is completely different.
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What's New in This Release: [ read full changelog ]
· Improved before-queue content filter performance. With "smtpd_proxy_options = speed_adjust", the Postfix SMTP server receives the entire message before it connects to a before-queue content filter. Typically, this allows Postfix to handle the same mail load with fewer content filter processes.
· Improved address verification performance. The verify database is now persistent by default, and it is automatically cleaned periodically. Under overload conditions, the Postfix SMTP server no longer waits up to 6 seconds for an address probe to complete.
· Support for reputation management based on the local SMTP client IP address. This is typically implemented with "FILTER transportname:" actions in access maps or header/body checks, and mail delivery transports in master.cf with unique smtp_bind_address values.
· The postscreen daemon (a zombie-blocker in front of Postfix) is still too rough for a stable release, and will be made "mature" in the Postfix 2.8 development cycle (however you can use Postfix 2.7 with the Postfix 2.8 postscreen and dnsblog executables and master.cf configuration; this code has already proven itself).