Cisco Cisco Email Security Appliance C160 Mode D'Emploi

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Cisco AsyncOS 9.1 for Email User Guide
 
Chapter 9      Using Message Filters to Enforce Email Policies
  Message Filter Rules
In the following example, at any given point in time, if the filter detects 
X
 or more outgoing messages 
from same envelope sender in the last one hour, the subsequent messages from the same envelope sender 
are dropped and discarded. 
In the following example, at any given point in time, if the filter detects 
X
 or more incoming or outgoing 
messages with identical subject in the last one hour, the administrator is notified for every subsequent 
message with identical subject. 
URL Reputation Rules 
Use a URL reputation rule to define message actions based on the reputation score of any URL in the 
message. For important details, see 
 in 
 
For these rules: 
msg_filter_name
: is the name of this message filter.
whitelist
 is the name of a defined URL list (via the 
urllistconfig
 command.) Specifying a 
whitelist is optional. 
To take action when the reputation service provides a score: 
Use the 
url-reputation
 rule. 
Filter syntax when using a 
url-reputation
 rule is: 
<msg_filter_name>: 
if url-reputation(<min_score>, <max_score>, '<whitelist>') 
{<action>}
Where: 
min_score
 and 
max_score 
are the minimum and maximum scores in the range for which the action 
should apply. The values that you specify are included in the range. 
Minimum and maximum scores must be between 
-10.0
 and 
10.0
To take action when the reputation service does not provide a score: 
Use the 
url-no-reputation
 rule. 
Filter syntax when using a 
url-no-reputation
 rule is: 
<msg_filter_name>: 
if url_no_reputation('<whitelist>') 
{<action>} 
URL Category Rule 
Use URL categories to define message actions based on the category of URLs in the message. For 
important details, see 
 
in 
 
f2 :  if header-repeats('mail-from', X, 'outgoing') {drop();}
f3: if header-repeats('subject', X) {notify('admin@xyz.com');}