I have been having the same problem as on thread
This is where mail gets stuck in the mail queue.
If the following is done
This almost always flushes the queue.
However this is not neat and I want a better work around until the other thread has identified the core problem.
I have used M1 and it was OK and I made the mistake of going live with M2
so I am manually running the process above every 30 minutes.
I would much rather
1) Stop postfix
2) Start postfix
3) Flush the queue
Then automate this in a cron job.
How do we stop and start postfix in the zimbra environment, do we need to be logged in as zimbra or root?
I know this is not the solution to the problem, but all hell breaks loose when I
forget to not run the manual flush.