NDP Neighbor Resolution Issue (UP_HOP179 / AS11967)

The provider resolved the issue.

We identified intermittent IPv6 packet loss (~7–9%) on our peering connection to UP_HOP179, caused by NDP neighbor state flapping (Reachable → Delay → Probing → Failed/Incomplete → Reachable) on the link-local next-hop. This resulted in severe latency spikes and dropped connections for traffic routed via this upstream.

As a mitigation, we have deprioritized this upstream by lowering its local preference, shifting affected traffic to our healthy upstream (AS6939). Traffic is currently stable via the alternate path.

We have reported the issue to the upstream provider, who confirmed the problem on their side and indicated a maintenance window will be required for a permanent fix. We will restore normal routing priority once the underlying NDP issue is resolved and confirmed stable.