BGP session not forming

[Isaac001]

Dear community,

I have a lab with 3 routers. R3,R4 and R5. R3 and R5 have bgp configuration as below. I have eigrp 100 running on all the routers and there is reachiblity to all IPs. R4 is BETWEEN R3 and R5. why can't a bgp session be formed between R3 and R5?

R3

router bgp 65100
bgp log-neighbor-changes
neighbor 10.13.1.2 remote-as 65200

R5

router bgp 65200
bgp log-neighbor-changes
no bgp default ipv4-unicast
neighbor 10.12.1.1 remote-as 65100
!
address-family ipv4
neighbor 10.12.1.1 activate
exit-address-family

!

BGP router identifier 192.168.3.1, local AS number 65100
BGP table version is 1, main routing table version 1

Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd
10.13.1.2 4 65200 0 0 1 0 0 never Idle

I have attached the routing tables, thanks experts!

Regards,

Isaac.

[Georg Pauwen]

Hello,

post the full running configs (sh run) of all routers, as well as a schematic drawing of your topology that shows how the routers are connected (and which interfaces are connected to which interfaces)...

[Harold Ritter · Accepted solution]

Hi @Isaac001 ,

Since this is an ebgp session you are trying to establish R3 and R5 you need to add the following configuration on R3 and R5.

R3:

router bgp 65100

neighbor 10.13.1.2 ebgp-multihop

R5:

router bgp 65200

neighbor 10.12.1.1 ebgp-multihop

Regards,

[Isaac001]

Harold,

Thank you, configured it and it immediately came up!

Regards,

Isaac.

[Harold Ritter]

You are very welcome @Isaac001 and thank you for the feedback