RESOLVED: Multiple services were experiencing issues in the europe-west2 region.
Incident began at 2026-10-19 23:00 and ended at 2026-10-20 05:08 (all times are US/Pacific ). Incident Report Summary On Monday, 19 Oct 2026 at 22:53 US/Pacific (Tuesday, 20 Oct 2026, 06:53 BST), a data center facility that hosts europe-west2-b, a zone within the europe-west2 cloud region, experienced an external electrical power disruption. This resulted in service unavailability for workloads located in this zone. The subsequent failover of these workloads to unaffected zones and alternate regions caused transient latency and elevated error rates across the broader europe-west2 region. The resolution of the main impact was completed within 6 hours and 8 minutes. Root Cause Facility architecture and background: The data center facility in the UK region hosts Cloud clusters serving the europe-west2-b zone, which form part of the multi-zonal europe-west2 Cloud region. The site relies on a 2N utility power architecture—where the facility has complete duplicate power paths for every critical load—backed by a central high-voltage generator bank managed by a dual-redundant Programmable Logic Controller (PLC). Primary utility power is supplied to the facility via two independent feeders (A and B), supplemented by a standby utility connection configured for manual campus-wide transfer during maintenance operations or emergency events. The two high-voltage primary feeders (A and B) terminate at separate primary intake switchboards capable of closed-loop operation if either board is taken offline. Switching between the primary and standby utility providers utilizes open transitions and key interlocks to prevent parallel connections across sources. Uninterruptible Power Supply (UPS) battery systems provide approximately five minutes of autonomous runtime. This bridge power ensures uninterrupted operation while the PLC detects utility undervoltage events, initiates diesel generator startup, synchronizes the generators, and transfers the site load. Prior to the utility disrupti