Home > Ticket 3 – BGP Neighbor

Ticket 3 – BGP Neighbor

May 4th, 2018 Go to comments

Configuration of R1:
router bgp 65001
no synchronization
bgp log-neighbor-changes
network 209.65.200.224 mask 255.255.255.252
neighbor 209.56.200.226 remote-as 65002
no auto-summary

check bgp neighborship. **** show ip bgp sum****
The neighbor’s address in the neighbor command is wrong under router BGP. (use ipv4 Layer 3)

Answer: need change on router mode on R1 neighbor 209.65.200.226

Ans1) R1
Ans2) BGP
Ans3) delete the wrong neighbor statement and enter the correct neighbor address in the neighbor command (change “neighbor 209.56.200.226 remote-as 65002″ to “neighbor 209.65.200.226 remote-as 65002″)

Comments (5) Comments
  1. Mujib
    January 11th, 2020

    even my BGP neighborship is up but I am not able to ping the internet server even my trace gets stop in ISP router.

    CAN ANYONE HELP ME

  2. Wa
    January 14th, 2020

    ip access-list extended edge_security
    deny ip 10.0.0.0 0.255.255.255 any
    deny ip 172.16.0.0 0.15.255.255 any
    deny ip 192.168.0.0 0.0.255.255 any
    deny ip 127.0.0.0 0.255.255.255 any
    permit ip host 209.65.200.241 any
    permit ip 209.65.200.224 0.0.0.3 any

  3. Majid
    January 21st, 2020

    @matty
    Question: How This is exactly what I was wondering. We should not be able to ping it as the address is wrong. Why can we still ping 209.65.200.226? lool

    Answer: As per the topology, the R1 and ISP routers are directly connected through serial interface having the IPs of 209.65.200.225 and 226. They should ping each other normally on serial interfaces even if IP routing is disabled on both routers. Here, the problem is that R1 cannot ping Web Server (209.65.200.241) due to the fact that BGP neighborship is not formed between R1 and ISP router.
    Solution is to look for any issues/problems in BGP neighbor formation if the physical link is up and running. By looking in the configuration, one can easily see that wrong neighbor statement is included in R1’s BGP config.
    Hope this helps.

  4. Dudeman1918
    February 13th, 2020

    @Marcus from Jan 26th. Connected routes aren’t redistributed into BGP by default, so if you wanted to ping either of the two IPs in 209.65.200.224/30 you wouldn’t be able to from any router except R1. To get that route into BGP, you need either the “redistribute connected” command under your BGP configuration or the network statement shown here.

    While it’s a detail that doesn’t strictly matter for the test (unless they tweak the question to ask e.g. why you can’t ping 209.65.200.226), his configuration is correct if your goal is to get end to end connectivity between every interface in the network.

  5. Mel Pipkin
    November 2nd, 2022

    Hello!