Network & Infrastructure / EVPN, VXLAN & Data Center Fabrics
MAC mobility sequence jumps and a hidden Layer-2 loop
An endpoint alternates between two VTEPs faster than a legitimate migration could explain. Increasing mobility sequences can reflect a loop or duplicated attachment rather than an actively moving VM.
Environment and inputs: BGP EVPN overlays on a routed underlay; supported route types and multihoming behavior depend on the network OS. Diagnostic/design example; not tested on production equipment.
Collect the evidence
Correlate MAC move events, sequence values, local port learning and host migration logs. Examine dual attachment, bridge configuration and any external Layer-2 path between the segments.
Explain the result
EVPN mobility resolves changing ownership, but repeated competing advertisements can be a symptom of duplicated traffic returning through another port. The highest sequence is not proof of correct physical ownership.
Plan the fix
Remove the unintended bridging path or duplicate attachment using the approved tenant topology. Retain platform mobility safeguards while determining the actual source of relearning.
Check the result and rollback
Verify stable ownership through normal traffic and one controlled migration. Revert containment if it isolates the intended active attachment, and confirm sequence churn does not simply move elsewhere.