====== Manage the postfix mailqueue ======

==== Display a list of queued mail, deferred and pending ====
  mailq
or
  postqueue -p

==== View message (contents, header and body) ====
Assuming the message has the ID XXXXXXX (you can see the ID form the QUEUE)
  postcat -vq XXXXXXXXXX

==== Process the Queue ====
  postqueue -f
or
  postfix flush

==== Halt/Resume Queue ====
If your server has very high load and you want to temporarily move all message from the incoming queue to the hold queue, use the command:
  postsuper -h ALL
To move the messages back to the incoming queue, use the command:
  postsuper -r ALL

==== Delete message(s) ====
Delete a message by message ID
  postsuper -d MessageID

Delete all queued mail
  postsuper -d ALL

Delete differed mail queue messages, those the system will retry later
  postsuper -d ALL deferred

Remove emails by sender (hacked account spamming?)
  mailq | tail +2 | grep -v '^ *(' | awk  'BEGIN { RS = "" } { if ($7 == “spamming@example.com” && $9 == “”) print $1 } ‘ | tr -d ‘*!’ | postsuper -d -

Remove emails by recipient (highly spammed account?)
  mailq | tail +2 | grep -v '^ *(' | awk  'BEGIN { RS = "" } { if ($8 == "spammed@example.com" && $9 == "") print $1 } ' | tr -d '*!' | postsuper -d -

Remove emails by sender hostname
  mailq | grep senderhostname | awk ‘{ print $1′} | postsuper -d -