In October 2026, one of Google Cloud's London zones went down for about six hours. One utility feed was already down for maintenance when a fault cut the other. That's exactly what generators are for. They didn't start. A misconfigured generator controller read voltage on the isolated feed, decided everything was fine, and stayed off while the UPS batteries drained.

I keep coming back to that one.

I work at Control Plane, and for the past few months I've been maintaining a tracker of major public cloud outages : AWS, Azure, Google Cloud, and Cloudflare, back to 2020, 56 of them sourced to the provider's own status page or post-mortem, the rest to press coverage. It's at 62 incidents now. Going through them one by one changed how I think about the word "redundant".

The backups were there.…