Hi all,
i found a site where route aggregation is explained.
R3(config-router)# aggregate-address 172.16.0.0 255.255.248.0 as-set
R4# show ip bgp
BGP table version is 12, local router ID is 10.0.0.10
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
*> 172.16.0.0/24 10.0.0.9 0 30 10 ?
*> 172.16.0.0/21 10.0.0.9 0 0 30 {10,20} ?
*> 172.16.1.0/24 10.0.0.9 0 30 10 ?
*> 172.16.2.0/24 10.0.0.9 0 30 10 ?
*> 172.16.3.0/24 10.0.0.9 0 30 10 ?
*> 172.16.4.0/24 10.0.0.9 0 30 20 ?
*> 172.16.5.0/24 10.0.0.9 0 30 20 ?
*> 172.16.6.0/24 10.0.0.9 0 30 20 ?
*> 172.16.7.0/24 10.0.0.9 0 30 20 ?The config shows a /21 was created from the aggregated addresses.
R3(config)# ip access-list standard Suppressed_Routes
R3(config-std-nacl)# permit 172.16.0.0 0.0.3.255
R3(config-std-nacl)# permit 172.16.6.0 0.0.1.255
R3(config)# route-map MySuppressMap
R3(config-route-map)# match ip address Suppressed_Routes
R3(config-router)# aggregate-address 172.16.0.0 255.255.248.0 as-set suppress-map
MySuppressMap
after the command was executed the result was:
R4# show ip bgp
Network Next Hop Metric LocPrf Weight Path
*> 172.16.0.0/21 10.0.0.9 0 0 30 {10,20} ?
*> 172.16.4.0/24 10.0.0.9 0 30 20 ?
*> 172.16.5.0/24 10.0.0.9 0 30 20 ? prefix that were suppressed was not advertised which is expected.
my question is what if i implement Unsuppress command instead of suppress with different approach
ip access-list standard UnSuppressed_Routes
permit 172.16.4.0 0.0.0.255
permit 172.16.5.0 0.0.0.255
route-map UNSUPPRESS
match ip address UnSuppressed_Routes
aggregate-address 172.16.0.0 255.255.248.0 summary-only as-set
neighbor 192.168.1.1 remote-as 20 unsuppress-map UNSUPPRESS
it will yield same result right?
Thanks all,
