Question 750
An EVPN service uses an all-active multihomed Ethernet segment. Observed: A customer-facing CE sees duplicate broadcast frames after a PE failure. Which acceptance observation best confirms that the proposed change worked?
Explanation
Correct Answer
This acceptance criterion tests the actual fault. The source evidence was A customer-facing CE sees duplicate broadcast frames after a PE failure. The correction addresses ethernet segment split-horizon or designated-forwarder behavior is incorrect; success requires only the elected forwarding path replicates BUM traffic and failover stays loss-limited.
Incorrect Answers
That observation would verify a separate fault involving pseudowire service label resolves to a broken mpls transport next hop. Its symptom is Pseudowire signaling remains Up but data drops on one transport path. For this case the actual issue is ethernet segment split-horizon or designated-forwarder behavior is incorrect, and the relevant success signal is Only the elected forwarding path replicates BUM traffic and failover stays loss-limited.
This result is useful in another case with evidence Data is discarded because the ingress and egress service framing differ. It does not test recovery from a customer-facing ce sees duplicate broadcast frames after a pe failure. Check instead whether only the elected forwarding path replicates BUM traffic and failover stays loss-limited.
It confirms an unrelated service correction: Ethernet segment identifier mismatch prevents correct multihoming coordination. The present case reports A customer-facing CE sees duplicate broadcast frames after a PE failure. Its completion test is Only the elected forwarding path replicates BUM traffic and failover stays loss-limited.