.Which Cisco Internetwork Operating System (IOS) command will you use to view the details of each interface on a router?
A. show controllers
B. show interfaces ethernet
C. show ip interface brief
D. show interfaces loopback
Correct Answer: C
The show ip interface brief command is used to view the details of each interface on a router. The output of the command displays the interfaces, the IP addresses configured on each
interface, the method, the status, and the protocol.
The following is a sample output of this command:
Interface IP-Address OK? Method Status Protocol
Ethernet0 10.105.00.5 YES NVRAM up up
Ethernet1 unassigned YES unset administratively down down
Loopback0 10.105.200.5 YES NVRAM up up
Serial0 10.105.100.5 YES NVRAM up up
Serial1 10.105.40.5 YES NVRAM up up
Serial2 10.105.100.5 YES manual up up
Serial3 unassigned YES unset administratively down down
The show controllers command is incorrect. The show controllers command is used to view hardware-related information on router and switch interfaces. It is useful for
troubleshooting and diagnosing issues with interfaces. One of the many useful pieces of information yielded by command is the type of cable connected to the interface. When you are
using a V.35 cable to connect two serial interfaces directly between two routers, one of the routers must be configured to provide the clocking on the line and it must be the router with
the DCE end of the cable. You can determine which router has that end by executing this command, which would display output similar to the following:
R2#show controllers serial 0
HD unit 0, idb = 0xDFE73, driver structure at 0xE52FF
Buffer size 1524 HD unit 0, V.35 DCE cable, clockrate 64000
In the above example, the DCE end of the V.35 cable is connected to this router. Therefore, this is the router that must be configured with a clockrate. The output demonstrates that
this requirement was already met.
The show interfaces ethernet command is incorrect because this command will display information only for Ethernet interfaces.
The show interfaces loopback command is incorrect because this command will show information regarding loopback interfaces only.
LAN Switching Fundamentals
Troubleshoot interface and cable issues (collisions, errors, duplex, speed)
Cisco > Cisco IOS IP Addressing Command Reference > show ip interface brief