Cisco CCNA (200-301)Network AccessMedium
A network engineer is configuring a new Cisco Catalyst switch, SW1, and wants to enable Link Layer Discovery Protocol (LLDP) globally to discover neighboring devices, including non-Cisco equipment. Which command should be used to enable LLDP globally on SW1?
- Acdp run
- Blldp run
- Cprotocol lldp
- Dlldp enable
Show answer & explanationAnswer & explanation
Correct answer: B. lldp run
The 'lldp run' command in global configuration mode enables LLDP globally on a Cisco IOS switch, allowing it to send and receive LLDP advertisements for discovering neighboring devices, including non-Cisco equipment.
Why the other options are wrong
- A. This command enables CDP (Cisco Discovery Protocol), which is Cisco-proprietary, not LLDP.
- C. This is not a valid Cisco IOS command to enable LLDP globally.
- D. While it sounds plausible, 'lldp enable' is not the correct global configuration command; 'lldp run' is used.
Global LLDP Enable
To enable Link Layer Discovery Protocol (LLDP) globally on a Cisco IOS device, the 'lldp run' command is used in global configuration mode.
- LLDP is an open standard discovery protocol.
- Used to discover neighbors, including non-Cisco devices.
- Enabled with 'lldp run' globally.
Memory trick: Let's Locate Diverse Peers (LLDP).