Postgrey is a Postfix policy server that implements greylisting. When a request for mail delivery is received by Postfix via SMTP, the triplet CLIENT_IP / SENDER / RECIPIENT is built. If it is the first time that this triplet is seen, or if the triplet was first seen less than 10 minutes ago, then the mail gets rejected with a temporary error. Hopefully, spammers or viruses will not try again later, even though such behavior is required per RFC.
| Tags | Communications Email Filters |
|---|---|
| Licenses | GPL |
| Operating Systems | POSIX |
| Implementation | Perl |
Recent releases


Release Notes: The logging format has been improved, and an important workaround for problems of exchange in dealing with greylisted email messages has been implemented. The whitelist has been updated, Exim support has been improved, and a greylist pre-seeding tool has been added.


Release Notes: Socket permissions with Net::Server 0.94 and later were fixed.


Release Notes: Support for Exim was added. Performance of the cleanup task was greatly improved.


Release Notes: The whitelist was updated with many new entries. A --privacy option was added. DB_TXN_NOSYNC is no longer used to work around an apparent bug in Berkeley-DB. A use of an uninitialized value was fixed. "permit_mynetworks" is used in the documentation.


Release Notes: This release fixes compatibility with Berkeley-DB < 4.1, fixes a crash in the database-cleanup routine, and updates the whitelist.