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Network L4 NETWORK-1496 · 9 min

A VLAN migration completes and one voice subnet still loops because LLDP-MED policy was inherited from the previous access policy template

Switchport mode is correct, but phones still learn the wrong voice VLAN via inherited LLDP-MED settings.

NetworkFoundation OpsLevel 4Free9 min
Scenario

Voice endpoints loop only on ports cloned from an older access template during a VLAN migration.

What to check first
  • Identify the primary failure signal in the The Port Was Moved to the New Neighborhood and the Phone Kept Listening to the Old Welcome Speech scenario.
  • Separate visible symptoms from the underlying technical dependency.
  • Describe the safest recovery path and the follow-up prevention work.
Checking checklist
  1. Summarize the current impact and the last known change.
  2. Collect direct evidence from logs, runtime state, and configuration before changing anything.
  3. Separate immediate recovery from permanent prevention work.
Recovery and prevention

Compare effective LLDP-MED policy before changing trunk native VLANs.

Questions worth viewing together
Should I translate commands, logs, or product names?

No. Keep commands, logs, file names, APIs, and product names unchanged, then explain the reasoning in the selected UI language.

What should the answer focus on?

State the root cause, the evidence that supports it, and the safest recovery direction.

Why can the scenario remain in the original language?

The source scenario is treated as an incident artifact. Guidance, checklist, hints, and explanations can be localized around it.