Cisco Cisco Email Security Appliance C190 用户指南
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Cisco IronPort AsyncOS 7.5 for Email Advanced Configuration Guide
OL-25137-01
Chapter 1 Customizing Listeners
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
SMTP “MAIL FROM” and “RCPT TO,” see
)
•
Advanced Configuration Options (optional settings for customizing the
behavior of the Listener, see
behavior of the Listener, see
•
LDAP Options (optional settings for controlling LDAP queries associated
with this Listener, see
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 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
IP port
The specific IP port used for connections to the listener. By
default, SMTP uses port 25 and QMQP uses port 628.
default, SMTP uses port 25 and QMQP uses port 628.
Listener Type:
Public
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.
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.
Private
Blackhole
“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
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.
Table 1-1
Criteria for Listeners