Configure Policy As_Path - Alcatel Router User Manual

Chapter : Policy Commands

configure policy as_path

This command configures the autonomous system path filter for BGP.
AS path access lists are used for matching the AS path attribute in a BGP route. An AS path access
list succeeds if any "permit" line in the list matches, or fails if any "deny" line matches. Matching
proceeds sequentially and stops at the first match.
The regular expression parameter is an as path regular expression. (For regular expression syntax,
see "AS Path Regular Expressions" on page 105.) Note that the regular expression must be enclosed
in quotation marks. The AS number is the smallest element of a
integer ranging from 0 to 65536; the
Any number of AS path access list lines may be declared. They are evaluated in the order declared. If
neither permit nor deny is specified, the default is "permit."
parameter definition
access_list Access list number
Range is 1 - 199.
number Sequence to insert or delete from an existing AS path entry.
Range is 0 - 65535.
action
deny
Deny AS path.
permit
Permit AS path.
regular_expression Regular expression to match the AS paths.
Enter a quoted string.
Refer to AS Path Regular Expressions on page 105 for more information about regular
expressions.
syntax:
[ no ] policy as_path access_list < n > number < n > action < deny | permit > regular_expression <
"string" >
example:
- /configure> policy as_path 1 120 permit "100"
Alcatel host
example:
- /configure> policy as_path 1 121 deny ".* 101 .*"
Alcatel host
applicable systems:
All models.
Alcatel
regular expression matcher is AS number-based.
Alcatel
regular expression. It is an
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