Configuring An As-Path Access-List - Motorola BSR 2000 Configuration And Management Manual

Release 1.0
Example
This configuration example
Access List 4 by specifying its permit and deny conditions. Access list 4 prohibits the
propagation of networks specified in the deny statements (10.0.0.0, 162.15.0.0, and
180.10.0.0) and permits all others.
Note: All lists have an assumed deny all entry as the last statement. If no
matches exist, the route or set is denied.
The following commands enable BGP, specify an autonomous system, and apply
Access List 4 to a neighbor. The example instructs the router to pass all network
information received from BGP neighbor 156.30.10.22 through access list 4.

Configuring an AS-path Access-list

The permit and deny conditions in an AS-path access list apply to AS numbers. The
neighbor filter-list command applies an AS-path access list for inbound and
outbound updates to a BGP neighbor. The match AS-path command adds a match
clause to a route map.
Use the ip as-path-access-list command to define an AS-path access list:
MOT (config)#ip as-path-access-list <1-199> {permit | deny} <LINE>
where:
Example
This example configures a router with two AS-path access lists. Routes that pass
AS-path access-list 1 are sent to one destination. Routes that pass AS-path access-list
2 are accepted from another destination. The commands below specify permit and
deny conditions for AS-path access lists.
526360-001-00 Rev. B
access-list 4 deny 10.0.0.0 0.255.255.255 any
access-list 4 deny 162.15.0.0 0.0.255.255 any
access-list 4 deny 180.10.0.0 0.0.255.255 any
access-list 4 permit any
router bgp 100
neighbor 160.25.15.10 distribute-list 4 in
1-199 is the regular expression access list number.
LINE is a valid path expression.
filters BGP updates from a BGP neighbor. It
MGBI
Configuring Routing Policy
configures
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