Connectivity Guide

Enable multipath
You can have one path to a destination by default, and enable multipath to allow up to 64 parallel paths to a destination. The show ip
bgp network command includes multipath information for that network.
• Enable multiple parallel paths in ROUTER-BGP mode.
maximum-paths {ebgp | ibgp} number
Enable multipath
OS10(config)# router bgp 10
OS10(conf-router-bgp-10)# maximum-paths ebgp 10
Route-map lters
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 lter 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 ltering criteria in ROUTER-BGP-NEIGHBOR-AF mode, then return to CONFIG-ROUTER-BGP
mode.
route-map map-name {in | out}
exit
• in—Enter a lter for incoming routing updates.
• out—Enter a lter 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 ltering 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 reector clusters
BGP route reectors are intended for ASs with a large mesh. They reduce the amount of BGP control trac. With route reection
congured properly, IBGP routers are not fully meshed within a cluster but all receive routing information.
Layer 3
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