Users Guide

Route-map filters
Filtering routes allows you to implement BGP policies. Use route-maps to control which routes the BGP neighbor or peer group
accepts and advertises.
1. Enter the neighbor IP address to filter routes in ROUTER-BGP mode.
neighbor ipv4-address
2. Enter Address Family mode in ROUTER-NEIGHBOR mode.
address-family {[ipv4 | ipv6] [unicast]}
3. Create a route-map and assign a filtering criteria in ROUTER-BGP-NEIGHBOR-AF mode, then return to CONFIG-ROUTER-
BGP mode.
route-map map-name {in | out}
exit
● in—Enter a filter for incoming routing updates.
● out—Enter a filter for outgoing routing updates.
4. Enter a peer template name in ROUTER-BGP mode.
template template-name
5. Enter Address Family mode.
address-family {[ipv4 | ipv6] [unicast]}
6. Create a route-map, and assign a filtering criteria in ROUTER-BGP-TEMPLATE-AF mode.
route-map map-name {in | out}
Filter BGP route
OS10(config)# router bgp 102
OS10(conf-router-bgp-102)# neighbor 40.1.1.2
OS10(conf-router-neighbor)# address-family ipv4 unicast
OS10(conf-router-bgp-neighbor-af)# route-map metro in
OS10(conf-router-bgp-neighbor-af)# exit
OS10(conf-router-bgp-102)# template ebgp
OS10(conf-router-template)# address-family ipv4 unicast
OS10(conf-router-bgp-template-af)# route-map metro in
Route reflector clusters
BGP route reflectors are intended for ASs with a large mesh. They reduce the amount of BGP control traffic. With route
reflection configured properly, IBGP routers are not fully meshed within a cluster but all receive routing information.
Configure clusters of routers where one router is a concentration router and the others are clients who receive their updates
from the concentration router.
1. Assign an ID to a router reflector cluster in ROUTER-BGP mode. You can have multiple clusters in an AS.
cluster-id cluster-id
2. Assign a neighbor to the router reflector cluster in ROUTER-BGP mode.
neighbor {ip-address}
3. Configure the neighbor as a route-reflector client in ROUTER-NEIGHBOR mode, then return to ROUTER-BGP mode.
route-reflector-client
exit
Layer 3
821