You are the administrator for a small VoIP network connected to an ITSP in the United States. The topology
consists of one voice router, a UCM, and three PoEcapable switches. All of the IP phones are receiving power.
However, none of the IP phones on the network are registering with UCM.
In which of the following fault domains should you begin troubleshooting? (Select the best answer.)
A.
the IP phones
B.
the cables connecting the IP phones to the switches
C.
the network switches that are connected to the IP phones
D.
the UCM configuration
Explanation:
Because none of the IP phones on the network are registering with Cisco Unified Communications Manager
(UCM), you should begin troubleshooting at the UCM configuration. Licensing problems or other configuration
issues could be preventing IP phones from registering with UCM. You might also begin troubleshooting at the
voice router instead of the UCM if all the IP phones on the network are able to register with UCM but are not
able to make calls beyond the router.
You would not begin troubleshooting at the IP phones, because all the IP phones are affected. If only one user
were experiencing the problem, you could begin troubleshooting the IP phone fault domain.
You would not begin the troubleshooting process by examining the cables connecting the IP phones to the
switch. You might check the cable connecting the IP phone to the switch or the switch port to which the cable is
connected if a single IP phone were a Power over Ethernet (PoE) device that was not receiving power from the
switch, or if Cisco Unified Communications Manager (UCM) reported that the device is of an unknown type.
You might also check the network cable and switch port if the device were powered by a power supply but
unable to register and download a configuration.
It is not likely that you would begin troubleshooting the network switches, because all users are affected by the
problem. You might begin troubleshooting the problem at the network switches if an entire department within an
organization were reporting a problem or if only the users connected to a given switch were experiencing a
problem.Reference:
https://www.cisco.com/c/en/us/obsolete/unified-communications/cisco-unified-communications-managerversion-7.1.html#wp1111505