Last Updated on July 31, 2021 by Admin 1
Which show command displays entries in a router’s Border Gateway Protocol (BGP) table?
- show ip bgp
- show ip bgp table
- show ip bgp topology
- show ip bgp summary
The correct command is show ip bgp.The BGP table lists all the paths that the BGP router has learned. Each destination network listed might have multiple possible paths listed. Given that the criteria are met for each destination network, BGP will choose a path to put in the IP routing table.The BGP table is in many ways analogous to EIGRP’s topology table in that it lists many known paths, not just the best path. Below is an example partial output of the show ip bgp command:
The following facts can be determined from this output:
All of the routes were redistributed into BGP from an IGP. In the status column (located to the left of the Network column and to right of the column where some lines have a > symbol) is a column that is either blank or has an i symbol. In this case, all of the columns are blank. If the status column is blank, then BGP learned the route from an external peer. If it has an i symbol, an iBGP neighbor advertised this path to the router. It was learned from an Interior Gateway Protocol (IGP) and was advertised as a result of executing a network statement on the neighbor under the router bgp context as shown below adding the 18.104.22.168 network under BGP 100.
R4(config)#router bgp 100 R4(config-router)#network 22.214.171.124
Four routes will be installed in the routing table. These routes have both an * symbol and a > symbol.
l in the status column. The * symbol indicates that the next hop is valid and the > symbol indicates that this is the best route.
The output is slightly different if you specify the network that you are interested in, as shown below in the show ip bgp 126.96.36.199 command output:
This output focuses solely on the route to the network 188.8.131.52 and provides the following pieces of information:
The neighbor that sent this route is at 192.168.1.1
The AS of the network where 184.108.40.206 is located is 5760
The IGP metric to reach the neighbor that sent this route is 886, as shown by the text 192.168.1.1 (metric 886)
The complete metric to 220.127.116.11 is 1652, as shown in the last line by Origin IGP, metric 1652
The commands show ip bgp table and show ip bgp topology are not valid Cisco commands.
The show ip bgp summary command displays the status of BGP connections.
Layer 3 Technologies
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