Cisco Cisco Email Security Appliance C160 Mode D'Emploi

“Black hole” listeners allow you to test your message generation systems and to also get a rough measure 
of receiving performance. Two types of black hole listeners are queueing and non-queueing. 

The queueing listener saves the message to the queue, but then immediately deletes it. Use a queuing 
listener when you are interested in measuring the performance of the entire injection portion of your 
message generation system. 

The non-queueing listener accepts a message, and then immediately deletes it without saving it. Use 
the non-queueing listener when you want to troubleshoot the connection from your message 
generation system to the appliance. 

For example, in 

, you could create a black hole listener “C” to mirror the private listener 

labeled “B.” A non-queueing version tests the performance path of the system from the groupware client 
to the groupware server to the appliance. A queueing version tests that same path and the appliance’s 
ability to enqueue messages and prepare them for delivery via SMTP. 

The following sections note operations that occur when a message is delivered. The 

trace

 command 

prints “

Message Enqueued for Delivery

” before this section. 

Global Unsubscribe per 
Domain and per User 

If any recipients you specified as input for the 

trace

 command match 

recipients, recipient domains, or IP addresses listed in the in the 
Global Unsubscribe feature, any unsubscribed recipient addresses are 
printed in this section. 

See 

When all processing has been printed, you are prompted with the final result. In the CLI, Answer 

 to 

the question, “Would you like to see the resulting message?” to view the resulting message.