Sendmail
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How To Flush Out All Email Messages From The Sendmail Queue
Sometimes email messages can be queued up with the Mail Transport Agent: "sendmail". The following command line can be used to manually try to immediately flush out All emails queued up by "sendmail". Even though a "sendmail" service may be running, this command is Ok to use, it will only run once and then terminate.
Try To Flush Out The Entire "sendmail" Queue:
[root@probe-222 root]# /usr/local/sbin/sendmail -q -v
How To Flush Out A Specific Email Message From The Sendmail Queue
"sendmail" can be told to only flush certain emails from the "queue" with an additional argument to "-q". One can flush email messages that match a specific recipient's address:
Try To Flush Out A Specific "sendmail" Queued Email Message:
[root@probe-222 root]# /usr/local/sbin/sendmail -qR "securecomputing.com" -v
All queued email messages with a recipient address that matches: "securecomputing.com" will be flushed out. You can also use "-qS" to match on the "sender" and "-qI" to match on the "queue ID".