LLDP (Link Layer Discovery Protocol) is a standard protocol used to advertise and receive network device information. Here's how LLDP behaves on ArubaOS-CX:
1. When is LLDP Added, Updated, or Deleted?
• Added: When an interface is enabled and LLDP is active on the port, the switch will start sending LLDP advertisements.
• Updated: LLDP updates occur periodically (default 30 seconds) or when there is a configuration change (e.g., VLAN changes, new neighbor detected).
• Deleted: LLDP entries are removed when a neighbor stops sending LLDP packets or when the interface goes down.
2. Investigating Frequent LLDP Messages in the Logs
• Check the LLDP timers:
• show lldp configuration → Verify advertisement intervals.
• Monitor LLDP Traffic:
• show lldp neighbors → Check active LLDP neighbors.
• show logging -r | include LLDP → Look for LLDP-related logs.
• LLDP Debugging:
• debug lldp → Monitor real-time LLDP events.
• Check for Misconfigurations:
• If LLDP-MED is enabled, some devices might trigger frequent LLDP updates.
• Spanning Tree Protocol (STP) changes can also cause LLDP messages.
3. Testing LLDP Add, Delete, and Update on CX-6200
• Add LLDP:
• Ensure LLDP is enabled:
config
interface <port>
lldp enable
• Verify LLDP is working:
show lldp neighbors
• Delete LLDP:
• Disable LLDP on a specific interface:
config
interface <port>
no lldp enable
• Clear LLDP neighbors manually:
clear lldp neighbors
• Update LLDP:
• Change the advertisement interval:
config
lldp transmit-interval <seconds>
• Modify LLDP settings (e.g., system description, port ID):
config
lldp system-description "New Description"
------------------------------
Deepak Pangare
------------------------------
Original Message:
Sent: Feb 10, 2025 01:46 AM
From: 陳 宜
Subject: CX-6200 log LLDP Question, please advise