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Network L6 NETWORK-1397 · 15 min

An MLAG pair carries normal traffic and a disaster-recovery test fails

Production looks healthy, yet the recovery-only VLAN path exists asymmetrically and fails only under failover conditions.

NetworkFoundation OpsLevel 6Free15 min
Scenario

A template split cleans up switch roles and later DR or orphan failover traffic fails only when the standby becomes relevant.

What to check first
  • Identify the primary failure signal in the The Recovery VLAN Was Ready on the Active Side and Imaginary on the Standby 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

Audit recovery-only VLAN treatment on both peers before blaming endpoint teaming.

Questions worth viewing together
What should you verify first when An MLAG pair carries normal traffic and a disaster-recovery test fails appears?

Community-field network problem inspired by MLAG operations cases where a recovery VLAN was trunked only on one peer. Recovery paths can drift silently because they are invisible during steady-state operation.

What usually causes An MLAG pair carries normal traffic and a disaster-recovery test fails in production?

Teams often blame host bonding or STP when the standby peer simply never carried the recovery VLAN correctly.

What should you document after resolving An MLAG pair carries normal traffic and a disaster-recovery test fails?

Template splits should be validated against every failover-only VLAN and orphan-port path.