- /usr/lib/sendmail -bv list| grep -v deliverable
- Causes sendmail to recursively expand the addresses in the mailing list named list. The -v with grep(1) causes all good (deliverable) addresses to be excluded and only bad addresses to be printed.
- /usr/lib/sendmail -bt -d0.4 </dev/null
- Causes sendmail to print its version, the
#defines used when it was compiled, and how it is interpreting the identity of the local machine.
- mailq -OMaxQueueRunSize=1
- Allows sendmail to quickly print how many messages are queued even when the queue contains thousands of messages.
- /usr/lib/sendmail -q -OTimeout.queuereturn=99d
- Flushes messages from an old queue (perhaps following a prolonged downtime) while preventing old messages from timing out in the queue.