ECS4660-28F_Management Guide-R03

C HAPTER 51 | IP Routing Commands
Policy-based Routing for BGP
– 1906 –
EXAMPLE
Console(config)#route-map RD permit 7
Console(config-route-map)#match metric 60
Console(config-route-map)#set weight 30
Console(config-route-map)#
match origin This command sets the originating protocol to match in routing messages.
Use the no form to remove this entry from a route map.
SYNTAX
match origin {egp | igp | incomplete}
no match origin
egp – Routes learned from exterior gateway protocols.
igp – Routes learned from internal gateway protocols.
incomplete – Routes of uncertain origin.
COMMAND MODE
Route Map
EXAMPLE
Console(config)#route-map RD permit 8
Console(config-route-map)#match origin igp
Console(config-route-map)#set weight 30
Console(config-route-map)#
match pathlimit as This command sets the maximum AS path length allowed for propagation
of more specific prefixes to match in routing messages. Use the no form to
remove this entry from a route map.
SYNTAX
match pathlimit as as-limit
no match pathlimit as
as-limit – Maximum AS path length. (Range: 1-4294967295)
COMMAND MODE
Route Map
COMMAND USAGE
◆ To perform inter-domain traffic engineering, a multi-homed site can
advertise its prefix to all of its neighbors via an aggregate address, and
also advertise more specific prefixes to a subset of its neighbors. The
longest match lookup algorithm then causes traffic for the more specific
prefixes to be forwarded to the subset of neighbors with the more
specific prefix.