Postfix logs all failed and successful deliveries to a logfile.
The file is usually called /var/log/maillog or /var/log/mail; the
exact pathname is defined in the /etc/syslog.conf file.
When Postfix does not receive or deliver mail, the first order
of business is to look for errors that prevent Postfix from working
properly:
% egrep '(warning|error|fatal|panic):' /some/log/file | more
Note: the most important message is near the BEGINNING of the
output. Error messages that come later are less useful.
The nature of each problem is indicated as follows:
-
"panic" indicates a problem in the software itself
that only a programmer can fix. Postfix cannot proceed until this
is fixed.
-
"fatal" is the result of missing files, incorrect
permissions, incorrect configuration file settings that you can
fix. Postfix cannot proceed until this is fixed.
-
"error" reports a fatal or non-fatal error condition.
Postfix cannot proceed until this is fixed.
-
"warning" indicates a non-fatal error. These are
problems that you may not be able to fix (such as a broken DNS
server elsewhere on the network) but may also indicate local
configuration errors that could become a problem later.
