Policy Framework Configuration Guide - Juniper Networks

Junos 10.4 Policy Framework Configuration Guide
Defining BGP Communities and Extended Communities for Use in Routing Policy Match
Conditions
To use a BGP community or extended community as a routing policy match condition,
you define the community as described in the following sections:
• Defining BGP Communities for Use in Routing Policy Match Conditions on page 104
• Defining BGP Extended Communities for Use in Routing Policy Match
Conditions on page 107
• Inverting Community Matches on page 109
Defining BGP Communities for Use in Routing Policy Match Conditions
To create a named BGP community and define the community members, include the
community statement:
community name {
invert-match;
members [ community-ids ];
}
You can include this statement at the following hierarchy levels:
• [edit policy-options]
• [edit logical-systems logical-system-name policy-options]
name identifies the community. It can contain letters, numbers, and hyphens (-) and can
be up to 255 characters long. To include spaces in the name, enclose the entire name in
quotation marks (“ ”).
community-ids identifies one or more members of the community. Each community ID
consists of two components, which you specify in the following format:
as-number:community-value;
• as-number—AS number of the community member. It can be a value from 0
through 65,535. For more information about configuring AS numbers, see the Junos
OS Routing Protocols Configuration Guide. You can use the following notation in
specifying the AS number:
• String of digits.
• Asterisk (*)—A wildcard character that matches all AS numbers. (In the definition
of the community attribute, the asterisk also functions as described in Table 17 on
page 106.)
• Period (.)—A wildcard character that matches any single digit in an AS number.
• Group of AS numbers—A single AS number or a group of AS numbers enclosed in
parentheses. Grouping the numbers in this way allows you to perform a common
operation on the group as a whole and to give the group precedence. The grouped
numbers can themselves include regular expression operators. For more information
104
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