Which commands would you use to determine the IP address and hostname of a directly connected switch
from which you received VLAN information? (Choose two. Each correct answer is part of the solution.)
A.
show vtp status
B.
show cdp neighbors detail
C.
show cdp neighbor status
D.
show vtp counters
E.
show cdp neighbor
Explanation:
The VLAN Trunking Protocol (VTP) is used to synchronize VLANs between switches, and the question implies
that VTP is being used in this environment. The show vtp status command will display the IP address of the
switch that last updated your VLAN database. The output of this command is as follows:
The “Configuration last modified by 10.1.1.2” output reveals the IP address of the switch from which you
received VLAN information. Once you know the IP address of the switch, you can use the show cdp neighbors
detail command to determine the hostname associated with this IP address. The output of this command is as
follows:
The show cdp neighbors detail command provides detailed information about directly connected Cisco devices.The detail option is required to provide the IP address of the neighboring devices, and indicates here that IP
address 10.1.1.2 is assigned to Device ID: SwitchB, which is the hostname for this device. SwitchB is the switch
from which you received VLANs.
Although not offered as an option, the show cdp entry* command will also display all directly connected devices
and will indicate the hostname and the IP address and platform, but will not indicate from which device VTP
information was received. Its output is shown below:
This command displays the same information as the show cdp neighbor detail command. It includes:
The IP address of the neighbor (in this case 10.1.1.2)
The port on which the CDP information was received (in this case FastEthernet0/4)
The platform (in this case a Cisco WS-C2950G-24 Switch)
The show vtp counters command is incorrect because it does not display information about neighboring
devices, nor information regarding from which switch VLANs were received.
The show cdp neighbor command is incorrect because the detail option is required to display the IP addresses
of neighboring devices.
The show cdp neighbor status command is incorrect because this is not a valid Cisco IOS command.
Objective:
LAN Switching Fundamentals
Sub-Objective:
Configure, verify, and troubleshoot VLANs (normal/extended range) spanning multiple switches
