Networking Issues - West Europe - Mitigated

Impact Statement: Between 02:34 UTC and 07:25 UTC on 16 June 2023, we identified a networking issue in West Europe region. Networking traffic to and from West Europe may have been affected and resources hosted in this region may have experienced availability failures, low throughput, or increased latencies. Preliminary Root Cause: We identified that network automation systems incorrectly determined that network links in West Europe region were not working properly and shut down the links. Regions are built with extensive redundancy, however enough links were taken out of service to cause congestion and impact to customer traffic. Mitigation: Engineers placed the links back into service and ensured that the network automation would not remove them again. The network recovered after the links were restored, and other services dependent on the network recovered shortly thereafter. Next Steps: We will continue to investigate to establish the full root cause and prevent future occurrences. Stay informed about Azure service issues by creating custom service health alerts: https://aka.ms/ash-videos for video tutorials and https://aka.ms/ash-alerts for how-to documentation