I have a backup mail server in case of a failure on the main one. In that case of failure, mails come on the backup server and stay there until the main one is back.
If I wait some times, the delivery will be done automatically as soon as the main server is back but it can be long. So how to force a send retry of all the mails?
For exemple : postqueue -p : give me a list of mails
I then tried postqueue -f (from man page : Flush the queue: attempt to deliver all queued mail.). It surely flushed the queue but mails were not been delivered...
postqueue -q. There is
sendmail -qto support sendmail syntax so postfix can completely replace sendmail, but that's a synonym. The different letters are jsut because postfix chose different ones than sendmail did.