Руководство Пользователя для Cisco Cisco Email Security Appliance C190

In addition to these criteria, you can also configure the following for each listener:

SMTP Address Parsing Options (optional settings for controlling parsing in 
SMTP “MAIL FROM” and “RCPT TO,” see 

)

Advanced Configuration Options (optional settings for customizing the 
behavior of the Listener, see 

LDAP Options (optional settings for controlling LDAP queries associated 
with this Listener, see 

Further, there are global settings that apply to all listeners, see 

 for more information.

When you create a listener, you specify the hosts that are allowed to connect to 
the listener through the Host Access Table (HAT). For public listeners, you also 
define all domains that the appliance will accept messages for using the Recipient 

The specific IP port used for connections to the listener. By 
default, SMTP uses port 25 and QMQP uses port 628.

Public and private listeners are used for most 
configurations. By convention, private listeners are 
intended to be used for private (internal) networks, 
while public listeners contain default characteristics 
for receiving email from the Internet. 

“Blackhole” listeners can be used for testing or 
troubleshooting purposes. When you create a 
blackhole listener, you choose whether messages are 
written to disk or not before they are deleted. (See 
“Testing and Troubleshooting” in the Cisco IronPort 
AsyncOS for Email Daily Management Guide for 
more information.) Writing messages to disk before 
deleting them can help you measure the rate of 
receiving and the speed of the queue. A listener that 
doesn’t write messages to disk can help you measure 
the pure rate of receiving from your message 
generation systems. This listener type is only 
available through the 

listenerconfig

 command in 

the CLI.