Cisco ASR 9000 Series Configuration Manual page 139

Implementing BGP
Storing updates from a neighbor works only if either the neighbor is route refresh capable or the
Note
soft-reconfiguration inbound command is configured. Even if the neighbor is route refresh capable and
the soft-reconfiguration inbound command is configured, the original routes are not stored unless the
always option is used with the command. The original routes can be easily retrieved with a route refresh
request. Route refresh sends a request to the peer to resend its routing information. The soft-reconfiguration
inbound command stores all paths received from the peer in an unmodified form and refers to these stored
paths during the clear. Soft reconfiguration is memory intensive.
SUMMARY STEPS
1. configure
2. router bgp as-number
3. neighbor ip-address
4. address-family { ipv4 | ipv6 } unicast
5. soft-reconfiguration inbound [ always]
6. commit
DETAILED STEPS
Command or Action
Step 1
configure
Step 2 router bgp as-number
Example:
RP/0/RSP0/CPU0:router(config)# router bgp
120
Step 3 neighbor ip-address
Example:
RP/0/RSP0/CPU0:router(config-bgp)#
neighbor 172.168.40.24
Step 4 address-family { ipv4 | ipv6 } unicast
Example:
RP/0/RSP0/CPU0:router(config-bgp-nbr)#
address-family ipv4 unicast
Step 5 soft-reconfiguration inbound [ always]
Example:
RP/0/RSP0/CPU0:router(config-bgp-nbr-af)#
soft-reconfiguration inbound always
OL-30423-03
Purpose
Specifies the autonomous system number and enters the BGP
configuration mode, allowing you to configure the BGP routing
process.
Places the router in neighbor configuration mode for BGP routing
and configures the neighbor IP address as a BGP peer.
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 (?).
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.
Cisco ASR 9000 Series Aggregation Services Router Routing Configuration Guide, Release 5.1.x
Configuring Software to Store Updates from a Neighbor
111