Which two components are used to identify a neighbor in a BGP configuration? (Choose two.)
A. autonomous system number
B. version number
C. router ID
D. subnet mask
E. IP address
Answer: AE
Explanation:
Use the show ip bgp neighbors (registered customers only) command to display information about the TCP and Border Gateway Protocol (BGP) connections and verify if the BGP peer is established. The output of the show ip bgp neighbors command below shows the BGP state as ‘Established’, which indicates that the BGP peer relationship has been established successfully.
R1-AGS# show ip bgp neighbors | include BGP
BGP neighbor is 10.10.10.2, remote AS 400, internal link BGP version 4, remote router ID 2.2.2.2
BGP state = Established, up for 00:04:20
BGP table version 1, neighbor version 1
R1-AGS#
The show ip bgp neighbors command has been used above with the modifier | include BGP. This makes the output more readable by filtering the the command output and displaying the relevant parts only.
In addition, the show ip bgp summary (registered customers only) command can also be used to display the status of all BGP connections, as shown below.
R1-AGS(9)# show ip bgp summary
BGP router identifier 10.1.1.2, local AS number 400 BGP table version is 1, main routing table version 1
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd 10.10.10.2 4 400 3 3 1 0 0 00:00:26 0
Explanation:
Use the show ip bgp neighbors (registered customers only) command to display information about the TCP and Border Gateway Protocol (BGP) connections and verify if the BGP peer is established. The output of the show ip bgp neighbors command below shows the BGP state as ‘Established’, which indicates that the BGP peer relationship has been established successfully.
R1-AGS# show ip bgp neighbors | include BGP
BGP neighbor is 10.10.10.2, remote AS 400, internal link BGP version 4, remote router ID 2.2.2.2
BGP state = Established, up for 00:04:20
BGP table version 1, neighbor version 1
R1-AGS#
The show ip bgp neighbors command has been used above with the modifier | include BGP. This makes the output more readable by filtering the the command output and displaying the relevant parts only.
In addition, the show ip bgp summary (registered customers only) command can also be used to display the status of all BGP connections, as shown below.
R1-AGS(9)# show ip bgp summary
BGP router identifier 10.1.1.2, local AS number 400 BGP table version is 1, main routing table version 1
Neighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd 10.10.10.2 4 400 3 3 1 0 0 00:00:26 0
