HP ProCurve Secure Router 7203 dl Advanced Management And Configuration Manual page 715

To use a route map to filter inbound routes according to network address and
prefix length, first create the prefix list and then enter these commands:
Syntax: route-map <mapname> <sequence number>
Syntax: match ip address prefix <listname>
Syntax: router bgp <local AS>
Syntax: neighbor <neighbor ID>
Syntax: route-map <mapname> in
Rather, or in addition to, filtering routes with a prefix list, you can filter routes
according to:
community
AS path
metric
To configure the router to accept only routes in a certain community or with
a certain AS path, you must configure a community or AS path list. (See
"Configuring a Community List" on page 13-88 or "Configuring an AS Path List"
on page 13-89.)
Next, create the route map entry (route-map <mapname> <sequence
number>) and match the entry to the appropriate list:
Syntax: match [as-path <listname> | community <listname>]
You can also configure the router to only accept routes with a particular
metric. Enter this command from the route map configuration mode context:
Syntax: match metric <value>
You can select a metric between 1 and 4294967295.
To complete the configuration, you must apply the route map to the neighbor
as inbound policy.
For example, you may not want to rely on an external neighbor to filter out
the routes that it is not supposed to advertise. You could configure the
following policy to do so:
ProCurve(config)# ip community-list External
ProCurve(config-comm-list)# deny no-advertise no-export local-as
ProCurve(config-comm-list)# route-map ExternalIn 10
ProCurve(config-route-map)# match community External
ProCurve(config-route-map)# router bgp 1
ProCurve(config-bgp)# neighbor 10.1.1.1
ProCurve(config-bgp-neighbor)# route-map ExternalIn in
IP Routing—Configuring RIP, OSPF, BGP, and PBR
Configuring BGP
13-101