BGP between Cisco routers on different subnets.

To illustrate this I will use GNS3, i used two Cisco Routers directly different subnets between them.
The topology is very simple:

Starting with the basic configuration, on R1:

NetworkLabs-1(config)#interface FastEthernet0/0
NetworkLabs-1(config-if)# ip address
NetworkLabs-1(config)# ip route FastEthernet0/0

Same thing on R2
 NetworkLabs-2(config)#interface FastEthernet0/0
NetworkLabs-2(config-if)# (config-if)#ip address
NetworkLabs-2(config-)#ip route FastEthernet0/0
At this stage we have ping back and forth between both Routers, now to the BGP
 NetworkLabs-1(config)#router bgp 1
NetworkLabs-1(config-router)# neighbor remote-as 2
 NetworkLabs-2(config)#router bgp 2
NetworkLabs-2(config-router)#neighbor remote-as 1
At this stage BGP will not come up, it will be stuck on idle state, to make it work all we need is to add " disable-connected-check" on both of the routers
 NetworkLabs-1(config-router)#neighbor disable-connected-check
NetworkLabs-2(config-router)#neighbor disable-connected-check

That's it.

Hope this post was helpful, If it was please consider a donation:
BTC Address: 1CnyMpjd1RntRDxSus2hu2aDMyzL4Kj29N

LTC Address: LUqrKbzGihTU2GEnL3EwsuuLHCsxCJMdtR

1 comment: