IronPort - Configuration Guide - AsyncOS 7.6.1

Chapter 5 Configuring the Gateway to Receive Email
Figure 5-6 Public Listener on C150/160 Appliance
Groupware server /
Message generation system
The Host Access Table (HAT):
Sender Groups and Mail Flow Policies
OL-25136-01
SMTP
Public Listener:
“MailInterface”
IP interface: MailNet (e.g. 192.168.2.1)
Ethernet interface: Data 2
IronPort C10 Email
Security appliance
Note This public listener uses SMTP protocol on Port 25 of the PublicNet IP
interface on the Data2 Ethernet interface to accept messages from the
Internet and to relay messages from internal systems in the .example.com
domain.
IP interface MailNet sends messages to destination hosts on the Internet
and to internal mail hosts.
Each listener that is configured on an appliance has properties that you can configure to modify the
behavior of the message it receives. As discussed in the Overview: Email Pipeline, page 4-1, one of the
first configurable features that influences a listener’s behavior is its Host Access Table (HAT).
The HAT maintains a set of rules that control incoming connections from remote hosts for a listener.
Every listener you create has its own HAT. HATs are defined for public and private listeners.
Entries in HAT are defined by this basic syntax:
Table 5-1 Basic HAT Syntax
Remote Host Definition Rule
The remote host definition is the way in which a remote host that is attempting to connect to the listener
is defined (for example, by a single IP address).
A rule defines whether the remote host specified can or cannot connect to the listener.
Cisco IronPort AsyncOS 7.6 for Email Configuration Guide
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