Policy Framework Configuration Guide - Juniper Networks

Junos 10.4 Policy Framework Configuration Guide
then {
preference 200;
accept;
}
term term2 {
then reject;
}
}
}
Match alternate paths to an AS and accept them after modifying the preference:
[edit]
policy-options {
wellington-alternate “1234{1,6} (56|47)? (78|101|112)* 9+”;
policy-statement from-wellington {
from as-path wellington-alternate;
}
then {
preference 200;
accept;
}
}
}
Match routes with an AS path of 123, 124, or 125 and accept them after modifying the
preference:
[edit]
policy-options {
addison "123–125";
policy-statement from-addison {
from as-path addison;
}
then {
preference 200;
accept;
}
}
}
Overview of BGP Communities and Extended Communities as Routing Policy Match
Conditions
A BGP community is a group of destinations that share a common property. Community
information is included as a path attribute in BGP update messages. This information
identifies community members and allows you to perform actions on a group without
having to elaborate upon each member. You can create a named community and include
it in a routing policy with the community match condition, which is described in “Configuring
Match Conditions in Routing Policy Terms” on page 41. For a list of the actions that can
be configured for communities, see “Configuring Actions That Manipulate Route
Characteristics” on page 49.
You can configure the standard community attribute and the extended communities
attribute for inclusion in BGP update messages. The standard community attribute is
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