CDP & LLDP Flashcards
Cisco Discovery Protocol and Link-Layer Discovery Protocol
What is the MAC address for CDP multicast messages?
0100.0CCC.CCCC
T/F: CDP is enabled on all Cisco devices by default
T
T/F: When a device receives a CDP message, it processes and discards the message (doesn’t forward)
T
CDP messages are never forwarded. Therefore, only adjacent neighbors can receive CDP messages from a device
T/F: When a device receives a CDP message, it forwards the message to other Cisco devices
F
CDP messages are never forwarded. Therefore, only adjacent neighbors can receive CDP messages from a device
What is the default CDP message interval?
60 seconds
What is the default CDP hold time
180 seconds
If a message isn’t received within this time frame, the neighbor is removed from the CDP table
T/F: There are 2 versions of CDP, and the default is V1
F
CDPv2 is the default
T/F: There are 2 versions of CDP, and the default is V2
T
CDPv2 is the default
Command to show CDP information such as version, holdtime, etc.
sh cdp
Command to show CDP neighbor information
sh cdp neighbors
Command to show CDP related traffic metrics, including packets I/O, errors, etc.
sh cdp traffic
Command to show CDP related information on interfaces
sh cdp interface
What command should you use to view the information in a Cisco device’s neighbor table?
sh cdp neighbors
Command to show verbose information on CDP neighbors
sh cdp neighbors detail
What CDP command should be used to identify a native VLAN mismatch?
sh cdp neighbors detail
What CDP command should be used to identify speed/duplex configuration mismatches?
sh cdp neighbors detail
What CDP command should be used to view verbose information about one CDP neighbor
sh cdp entry neighbor-hostname
What is the output of
sh cdp
Basic CDP information, including timers, version, etc.
What is the output of
sh cdp traffic
How many CDP messages have been sent and receives, and errors
What is the output of
sh cdp interface
Displays which interfaces CDP is enabled on, and related per-device information
What is the output of
sh cdp neighbors
Lists CDP neighbors and basic information about each neighbor, including hostname and what port they are connected to on both sides
What is the output of
sh cdp neighbors detail
Lists each CDP neighbor with verbose, detailed information
What is the output of
sh cdp entry hostname
Displays the same information as sh cdp neighbors detail, but for only the neighbor with the specified hostname
T/F: If running all Cisco devices and CDP use is desired, then configuration is required on each device
F
CDP is configured as necessary by default on all Cisco devices
Command to disable CDP on an entire device
from global config mode: no cdp run