Cisco NCS 5500 Series

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
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 5
soft-reconfiguration inbound [ always]
Example:
RP/0/RP0/CPU0:router(config-bgp-nbr-af)# soft-reconfiguration inbound always
Configures the software to store updates received from a specified neighbor. Soft reconfiguration inbound causes the
software to store the original unmodified route in addition to a route that is modified or filtered. This allows a “soft clear”
to be performed after the inbound policy is changed.
Soft reconfiguration enables the software to store the incoming updates before apply policy if route refresh is not supported
by the peer (otherwise a copy of the update is not stored). The always keyword forces the software to store a copy even
when route refresh is supported by the peer.
Step 6
commit
Log Neighbor Changes
Logging neighbor changes is enabled by default. Use the log neighbor changes disable command to turn off
logging. The no log neighbor changes disable command can also be used to turn logging back on if it has
been disabled.
BGP Route Reflectors
BGP requires that all iBGP speakers be fully meshed. However, this requirement does not scale well when
there are many iBGP speakers. Instead of configuring a confederation, you can reduce the iBGP mesh by
using a route reflector configuration. With route reflectors, all iBGP speakers need not be fully meshed because
there is a method to pass learned routes to neighbors. In this model, an iBGP peer is configured to be a
route reflector responsible for passing iBGP learned routes to a set of iBGP neighbors.
BGP Configuration Guide for Cisco NCS 5500 Series Routers, IOS XR Release 6.2.x
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Implementing BGP
BGP Route Reflectors