Postfix blocking on certain mails
I have a strange problem with my Postfix mailserver (version 2.3.8). In fact, it blocks on certain mails. I traced the problem down to this:
- the mail enters
- the mail is passed and scanned by Amavis-New
- the mail comes back to "virtual" and should be delivered
- then the "virtual" command blocks an the CPU goes up to 100%
Most of the mails do pass the system correctly, but a few get stuck. Performance is no matter, as there are (actually) only a few 100 requests per hour.
I tried to read the log files (/var/log/mail.log) but it contains no relevant data!
I temporary added the line "daemon_timeout=180" to the /etc/postfix/main.cf file in order to regain control over the server after some time, but this is no solution, as the mails are not getting delivered when the watch-dog kill the blocking command.
Some more details about my configuration:
- virtual delivery using LDAP
- Amavis-New via SMTP
- Postfix 2.3.8 with VDA-patch
I hope somebody could give me a helping hand ....