Cisco Cisco Email Security Appliance C160 Mode D'Emploi

Entries in HAT are defined by this basic syntax: 

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. 

Extending the basic syntax, HATs in AsyncOS support the ability to create named 
sets of remote host definitions; these are called sender groups. Named sets of 
access rules combined with parameter sets are called mail flow policies. This 
extended syntax is illustrated in 

The order that rules appear in the HAT is important. The HAT is read from top to 
bottom for each host that attempts to connect to the listener. If a rule matches a 
connecting host, the action is taken for that connection immediately. 

Predefined and custom entries you place in the HAT are entered above the final 
“ALL” host entry. 

For all public listeners you create, by default, the HAT is set to accept email from 
all hosts. For all private listeners you create, by default, the HAT is set up to relay 
email from the host(s) you specify, and reject all other hosts.