soft-reconfig inbound

[gauravprakash]

For the received-routes option to work, the router on which the command is used must have the neighbor neighbor-id soft-reconfiguration inbound BGP subcommand configured for the other neighbor.

Hence does that mean the changed / new routes will not be recevied till soft-reconfig inbound is configured...??

[vladrac-ccna]

Hello this command will only affect updates incoming your router.

so if you change inbound filters or your peer change its outbound filters , you need to do a clear ip bgp to make this changes work.

So, using clear ip bgp * soft in its recommended in order to avoid clearing the session with your peer.

"A traditional requirement of BGP was resetting the neighbors' TCP connection in order for a

policy change to take effect (clear ip bgp [* | address | peer-group]). Clearing the sessions in

this manner restarts the neighbor negotiations from scratch, invalidates the associated portions

of the IP forwarding cache, and causes a major impact on the operation of live networks."

"BGP soft reconfiguration is one approach that lets policies be configured and activated without resetting the BGP TCP session. This allows new policies to take effect without significantly affecting the network. Soft configuration can be applied in two different ways inbound and outbound"

I wouldnt recommend using this soft-reconfig command, as it demands memory.

new IOS use a new capability called BGP Route Refresh, so you dont need to use soft-reconfiguration inbound.

Check if your routers support this feature with:

show ip bgp neighbors

look for:

Neighbor capabilities:

Route refresh: advertised and receive

HTH,

if it does please rate this post.

Vlad

[viettel_adm]

When you change something in IP BGP, dont forget command clear ip bgp xxx.xxx.xxx.xxx soft [ in | out]. This is very important command in BGP update.

In your case, use command soft-reconfig inbound , the route you want to check will come in to buffer before come to routing table. If you use show ip bgp xxx.xxx.xxx.xxx is the route you want to check, you will see one entry in BGP table with soft-config.

When finish checking route, dont forget no ip bgp ... soft-reconfig inbound in sub BGP mode. If this command still in your config, performance in your router will higher than normal.