BGP neighborship issue

[tanmoymm91]

R1 ( AS no- 100) is having e-bgp peering with R2 (AS no- 200) 
BGP Is up and running in between 

one of the network (10.1.1.0/24) is advertising by R1 towards , R2 is accepting the same .

But when i check the routing table on R2 i am not seeing that network on the routing table .

what may be the issue here ?

P.S there is no filtering applied on R2 .

[M02@rt37]

Hello @tanmoymm91 

Considering you have no filtering apply on R2, please share the output:

R1: #sh ip bgp neighbor <ip_address_neighbor_R2> advertised-routes

=>[10.1.1.0/24] should be display.

If not, make sure you have the command #network 10.1.1.0 mask 255.255.255.0 on your BGP instance on R1.

Make sure that [10.1.1.0/24] is in the R1's RIB. 

If you have Filtering on R1 side (outbound), please share also the configuration.

[tanmoymm91]

Hi ,

there is no filtering apply on R1 side.

as i said earlier R1 is advertising the route to R2 and R2 is accepting the same , is there any possible options to check on R2 side ?

Note : i cant share any output here as all related to productions 

[M02@rt37]

@tanmoymm91,

R2: #sh ip bgp <ip_address_neighbor_R1> received routes

Is this eBGP multihoping?

Verify the BGP path selection process on R2. BGP uses various attributes to select the best path for a given network. Check if any attributes, such as local preference, AS path, or MED, might be affecting the selection of the advertised network by R2. Compare the attributes of the advertised network with other networks that are successfully appearing in the routing table on R2.

[MHM Cisco World]

it accept the path and mark it as best-path but it can put it to RIB-failure. 
the R2 have learn this prefix via direct connect or static route 

[Harold Ritter]

Hi @tanmoymm91 ,

You can do a "show bgp ipv4 unicast 10.1.1.0/24" on R2 to find out what is the issue with this specific prefix.

Regards,