Whenever you’re studying for your personal BSCI Test and CCNP certification, you rapidly know that BGP is a complete new environment from everything you’ve previously studies. One matter that from time to time confuses CCNP candidates is each time a BGP route reflector ought to be configured.
In the following instance, the routers R1, R2, and R3 are all in BGP AS one hundred. This isn't an entire mesh, even so. You can find peer interactions amongst R1-R2 and R1-R3, but not amongst R2 and R3. R3 is promoting network three.3.three.0/24 via BGP, as well as the route is witnessed on R1. R1’s iBGP neighbor, R2 would not see the route.
A basic 사설토토 rule of BGP is https://en.search.wordpress.com/?src=organic&q=토토사이트 usually that a BGP speaker are unable to market a path to an iBGP neighbor if that route was realized from An additional iBGP neighbor. Configuring R1 for a route reflector allows us to avoid this rule. The whole route reflector procedure is transparent to the clients, and no configuration is important on These clientele. We’ll configure R1 being a route reflector for equally R2 and R3.
R1(config)#router bgp 100
R1(config-router)#neighbor 172.12.123.2 route-reflector-consumer
3d18h: %BGP-5-ADJCHANGE: neighbor 172.twelve.123.two Down RR shopper config alter
R1(config-router)#neighbor 172.12.123.3 route-reflector-client
3d18h: %BGP-five-ADJCHANGE: neighbor 172.12.123.3 Down RR consumer config transform
The BGP adjacencies do appear down when this configuration is added, so this isn’t some thing you need to do all through a peak visitors time.
After the adjacencies come back up, R2 may have the route to three.3.3.0/24.
You will discover other possible methods to this iBGP limitation, including configuring BGP confederations. These solutions are commonly utilized on greater BGP deployments and with other fears in your mind, even though, and configuring route reflectors serves this goal just as effectively.