December 21, 2013

Lab 16: BGP Weight Modfication

Configure BGP on all routers. After the configuration, R1's BGP routing table will be like this:

R1#show ip bgp
BGP table version is 2, local router ID is 13.0.0.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path
*>i192.168.0.1/32   10.0.0.2                 0    100      0 i
* i                 13.0.0.2                 0    100      0 i

As you see, 10.0.0.2 (R2) is the next-hop for 192.168.0.1. Let's modify weight on R1:

access-list 10 permit 192.168.0.1

route-map RM_WEIGHT permit 10
 match ip address 10
 set weight 30

router bgp 100
 neighbor 13.0.0.2 route-map RM_WEIGHT in

As a result, 13.0.0.2 (R3) becomes the next-hop for 192.168.0.1 because the weight for R3 (30) is higher than R2:

R1#sh ip bgp
BGP table version is 2, local router ID is 13.0.0.1
Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,
              r RIB-failure, S Stale
Origin codes: i - IGP, e - EGP, ? - incomplete

   Network          Next Hop            Metric LocPrf Weight Path
* i192.168.0.1/32   10.0.0.2                 0    100      0 i
*>i                 13.0.0.2                 0    100     30 i

# DOWNLOAD LAB 16 GNS3 FILE