Postfix daemon processes run in the background, and log problems
and normal activity to the syslog daemon. The names of logfiles
are specified in /etc/syslog.conf. At the very least you need
something like:
/etc/syslog.conf:
mail.err /dev/console
mail.debug /var/log/maillog
IMPORTANT: the syslogd will not create files. You must create
them before (re)starting syslogd.
IMPORTANT: on Linux you need to put a "-" character before
the pathname, e.g., -/var/log/maillog, otherwise the syslogd
will use more system resources than Postfix does.
Hopefully, the number of problems will be small, but it is a good
idea to run every night before the syslog files are rotated:
# postfix check
# egrep '(reject|warning|error|fatal|panic):' /some/log/file
-
The first line (postfix check) causes Postfix to report
file permission/ownership discrepancies.
-
The second line looks for problem reports from the mail
software, and reports how effective the relay and junk mail access
blocks are. This may produce a lot of output. You will want to
apply some postprocessing to eliminate uninteresting information.
The
DEBUG_README
document describes the meaning of the "warning" etc. labels in
Postfix logging.