Bgp Cost Community; Configure Bgp Cost Community - Cisco NCS 5500 Series Configuration Manual

Implementing BGP
Specifies the autonomous system number and enters the BGP configuration mode, allowing you to configure the BGP
routing process.
Step 3 neighbor ip-address
Example:
RP/0/RP0/CPU0:router(config-bgp)# neighbor 172.168.40.24
Places the router in neighbor configuration mode for BGP routing and configures the neighbor IP address as a BGP peer.
Step 4 remote-as as-number
Example:
RP/0/RP0/CPU0:router(config-bgp-nbr)# remote-as 206
Creates a neighbor and assigns a remote autonomous system number to it.
Step 5 address-family { ipv4 | ipv6 } unicast
Example:
RP/0/RP0/CPU0:router(config-bgp-nbr)# address-family ipv4 unicast
Specifies either an IPv4 or IPv6 address family unicast and enters address family configuration submode.
To see a list of all the possible keywords and arguments for this command, use the CLI help (?).
Step 6 next-hop-self
Example:
RP/0/RP0/CPU0:router(config-bgp-nbr-af)# next-hop-self
Sets the next-hop attribute for all routes advertised to the specified neighbor to the address of the local router. Disabling
the calculation of the best next hop to use when advertising a route causes all routes to be advertised with the local
network device as the next hop.
Step 7
commit

BGP Cost Community

The BGP cost community is a nontransitive extended community attribute that is passed to internal BGP
(iBGP) and confederation peers but not to external BGP (eBGP) peers. The cost community feature allows
you to customize the local route preference and influence the best-path selection process by assigning cost
values to specific routes. The extended community format defines generic points of insertion (POI) that
influence the best-path decision at different points in the best-path algorithm.
BGP Cost Community Reference, on page 134

Configure BGP Cost Community

BGP receives multiple paths to the same destination and it uses the best-path algorithm to decide which is the
best path to install in RIB. To enable users to determine an exit point after partial comparison, the cost
provides additional conceptual details on BGP cost community.
BGP Configuration Guide for Cisco NCS 5500 Series Routers, IOS XR Release 6.2.x
BGP Cost Community
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