Prerequisites: CCNP level skills.
Topology
Configure R5 in such way, that if BGP in R3 does not support 'Route Refresh' message, it can still apply inbound policy without asking R5 to re-send their BGP prefixes.
Solution
Task 1
Configure R5 in such way, that if BGP in R3 does not support 'Route Refresh' message, it can still apply inbound policy without asking R5 to re-send their BGP prefixes.
Pic. 2 - BGP Before Applying Configuration.
R5 Configuration:
!
router bgp 50
no synchronization
bgp router-id 172.16.105.5
bgp log-neighbor-changes
network 172.16.105.0 mask 255.255.255.0
neighbor 10.1.35.3 remote-as 123
neighbor 10.1.35.3 soft-reconfiguration inbound
no auto-summary
no synchronization
bgp router-id 172.16.105.5
bgp log-neighbor-changes
network 172.16.105.0 mask 255.255.255.0
neighbor 10.1.35.3 remote-as 123
neighbor 10.1.35.3 soft-reconfiguration inbound
no auto-summary
!
Verfication:
Pic. 3 - BGP After Applying Configuration.
This command creates the exact copy of the BGP table. This causes high memory utilization but allows to apply inbound filtering on R5 without tearing down the session if the Route-Refresh messages are not supported on R5.
