Helo
I have network a.b.c.d/23 in my bgp configuration on my c28xx
On the same router on my LAN interface i'd like divide clas /23 on some subnets 4x a.b.c.d/25 etc and i have problem. When i configure subnets , my bgp stop advertise my prefix /23. When i delete subnets and i configure a.b.c.1/23 bgp works good.
There is possible to advertise in BGP prefix /23 and simultaneously have some subnets ?
thx for help
best regards
Pet
pomidorek pisze:
some outputs i conf
sh ip route C A.B.C.0/24 is directly connected, GigabitEthernet0/0 C A.B.C+1.0/24 is directly connected, Vlan2
sh ip bgp neighbors [ip] advertised-routes
Total number of prefixes 0
my conf router bgp [as] no synchronization bgp router-id [ip] bgp log-neighbor-changes network A.B.C.0 mask 255.255.254.0 neighbor [ip] remote-as [as] neighbor [ip] next-hop-self neighbor [ip] filter-list 4 in no auto-summary
Pet
Pet,
Can you post your bgp configuration as well as your 'show ip bgp' output?
neteng
sh ip route C 192.168.10.0/24 is directly connected, GigabitEthernet0/0 C 192.168.11.0/24 is directly connected, Vlan2
sh ip bgp neighbors [20.20.20.1] advertised-routes
Total number of prefixes 0
my conf router bgp [as] no synchronization bgp router-id [192.168.10.1] bgp log-neighbor-changes network 192.168.10.0 mask 255.255.254.0 neighbor [20.20.20.1] remote-as [as] neighbor [20.20.20.1] next-hop-self neighbor [20.20.20.1] filter-list 4 in no auto-summary
Pet
Pet,
ok I correct above Pet
BGP network statement causes the local route to be advertised by BGP ONLY if the route is in the RIB (main routing table) when you split the subnet then the original route is no longer in the RIB
All you need to do is create a summary route in the RIB for the original /23 subnet:
ip route 192.168.10.0 mask 255.255.254.0 null0
router bgp network 192.168.10.0 mask 255.255.254.0
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