Cisco Cisco Email Security Appliance C160 Guía Del Usuario
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Cisco IronPort AsyncOS 7.1 for Email Advanced Configuration Guide
OL-22164-02
Chapter 5 Using Message Filters to Enforce Email Policies
Note that you can omit any alternative actions:
Example Syntax
Purpose
expedite2:
filter name
if ((not (recv-listener ==
'InboundMail')) and
(not (recv-int == 'notmain')))
rule specification
{
alt-src-host('outbound2');
skip_filters();
}
action specification
You can combine several filters in sequence within a single text file, one following
the other.
the other.
You must enclose the values in filters in either single or double quotation marks.
Single or double quotation marks must be equally paired on each side of the value;
for example, the expressions
Single or double quotation marks must be equally paired on each side of the value;
for example, the expressions
notify('customercare@example.com')
and
notify("customercare@example.com")
are both legal, but the expression
notify("customercare@example.com')
causes a syntax error.
Lines beginning with a ‘
#
’ character are considered comments and are ignored;
however, they are not preserved by AsyncOS as can be verified by viewing a filter
via
via
filters -> detail
.
Message Filter Processing
When AsyncOS processes message filters, the content that AsyncOS scans, the
order of the processing, and the actions taken are based on several factors:
order of the processing, and the actions taken are based on several factors:
•
Message filter order. Message filters are maintained in an ordered list. When
a message is processed, AsyncOS applies each message filter in the order it
appears in the list. If a final action occurs, no further action is taken on the
message. For more information, see
a message is processed, AsyncOS applies each message filter in the order it
appears in the list. If a final action occurs, no further action is taken on the
message. For more information, see
•
Prior processing. Actions performed on AsyncOS messages may add or
remove headers before the message filter is evaluated. AsyncOS processes the
message filter process on the headers that are present in the message at the
time of processing. For more information, see
remove headers before the message filter is evaluated. AsyncOS processes the
message filter process on the headers that are present in the message at the
time of processing. For more information, see
.