Quanah Gibson-Mount:
> This is extremely difficult to reproduce, but it does happen occasionally
> -- We will tell postfix to stop, and once that is complete, a "postdrop"
> process will sometimes remain, and will run until it is manually killed.
>
> Is this an expected behavior of postdrop -- That after the master postfix
> is stopped, it is expected sometimes that it may continue running,
> regardless?
This is 100% intentional. The Postfix sendmail command MUST NOT
drop mail on the floor while the mail system is down.
For example there are programs that run at boot time that rely on
the availability of sendmail command-line submission, such as text
editors that want to send "how to recover your session" email.
Other daemons such as cron may be running while the Postfix daemons
are down for whatever reason. Their mail should not be lost, either.
Wietse
