Cannot advertise networks in BGP?

[jjevans1]

Hello All,

I have a lab setup and I am trying to advertise the 192.168.30.X and 192.168.40.X networks from the C4331-Edge to the C2911-ISP-RTR

Also, I am trying to advertise the 75.75.75.X network from the C2911-ISP-RTR to the C4331-Edge-RTR.

I have tried no auto summary on both. Loopback interfaces on both. I have specifically added the mask on network statement but it does not show on the running config.

I am running out of ideas.

Any insight as to how I can advertise these routes will be greatly appreciated.

Thank you,

J

[Martin L]

is next hop reachable ?  Before a router does BGP process decision, it must check next hop. if it does not have a route to the next hop for your route x , it will reject such route. 

Regards, ML
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[jjevans1]

Yes I can ping the next hops interface in each direction on each of the opposing devices. 

[MHM Cisco World]

both router not advertise the same prefix appear in RIB, the ISR4000 and 2911 not advertise the prefix.

[Harold Ritter]

Hi @jjevans1 ,

For the BGP network statement to originate the route, there needs to be a perfect match between the network statement and a route in the routing table. For instance, on C2911-ISP-RTR you have two routes in the routing table for prefix 75.75.75.0, but one is with a /32 mask (lo0) and the other one is with a /26 mask (gi0/2), while the bgp network statement is with a /24 mask. There is no perfect match between statement and the routing table, so BGP does not originate the route. The solution is to add the following configuration under router bgp.

C2911-ISP-RTR:

router bgp 2003

network 75.75.75.75 mask 255.255.255.255

or

network 75.75.75.0 mask 255.255.255.192

C4331-Edge-RTR-A:

router bgp 1969

network 192.168.30.1 mask 255.255.255.255

network 192.168.40.1 mask 255.255.255.255

Regards,

[paul driver]

Hello

tou need to advertise the loopbacks with correct network mask - 255.255.255.255