# Monitor Messages

You can monitor messages processed by a destination as they are sent, received, or acknowledged.

You can also monitor messages that have prematurely exited due to expiration, being discarded, or a `maxRedelivery` failure.

The `$sys.monitor` topic for monitor messages has the following format:

    $sys.monitor.D.E.destinationName

where D is the type of destination, E is the event you wish to monitor, and destinationName is the name of the destination whose messages you wish to monitor.

Copyright © Cloud Software Group, Inc. All rights reserved.