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Network L5 NETWORK-113 · 19 min

A campus overlay fabric duplicates the anycast gateway across sites with overlapping VNIs and east-west traffic misroutes intermittently

Local routing works most of the time, but some flows take the wrong site path because fabric identifiers are no longer unique per domain.

NetworkFoundation OpsLevel 5Free19 min
Scenario

Local routing works most of the time, but some flows take the wrong site path because fabric identifiers are no longer unique per domain.

What to check first
  • Identify the primary failure signal in the Overlay Identity Collision 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

Choose the smallest safe recovery action first, then record the prevention work that reduces repeat incidents.

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.