Hi everyone, I have deployed ASSP to improve Anti-Spam feature for our mail systems (running Zimbra). I have an issue related to SMTP connections between ASSP and Zimbra's Postfix.
After receiving EHLO command from one host running ASSP, another host running Postfix cannot continue to connect to ASSP to get more SMTP commands (the connection is disconnect ed). Here is our system topology: Internet -> SMTP Proxy Server (ASSP) -> SMTP Server (Zimbra) -> Mail Server (Zimbra) Here is the content of /var/log/mail.log file: Jun 28 09:55:33 mail postfix/smtpd[19834]: smtp_get: timeout Jun 28 09:55:33 mail postfix/smtpd[19834]: > unknown[192.168.100.11]: 421 4.4.2 mail.test.com Error: timeout exceeded Jun 28 09:55:33 mail postfix/smtpd[19834]: match_hostname: unknown ~? 127.0.0.0/8 Jun 28 09:55:33 mail postfix/smtpd[19834]: match_hostaddr: 192.168.100.11 ~? 127.0.0.0/8 Jun 28 09:55:33 mail postfix/smtpd[19834]: match_hostname: unknown ~? 192.168.100.0/24 Jun 28 09:55:33 mail postfix/smtpd[19834]: match_hostaddr: 192.168.100.11 ~? 192.168.100.0/24 Jun 28 09:55:33 mail postfix/smtpd[19834]: timeout after EHLO from unknown[192.168.100.11] Jun 28 09:55:33 mail postfix/smtpd[19834]: abort all milters Jun 28 09:55:33 mail postfix/smtpd[19834]: milter8_abort: abort milter inet:127.0.0.1:8092 Jun 28 09:55:33 mail postfix/smtpd[19834]: disconnect event to all milters Jun 28 09:55:33 mail postfix/smtpd[19834]: milter8_disc_event: quit milter inet:127.0.0.1:8092 Jun 28 09:55:33 mail postfix/smtpd[19834]: disconnect from unknown[192.168.100.11] P.S. I researched another cases to test SMTP connections between ASSP and Postfix/Sendmail, they worked perfectly. Thanks for your help. Regards, N. Thang