Power cut knocks out a Google Cloud zone in London for six hours

Google Cloud suffered a 6-hour, 10-minute outage in its europe-west2 region, in London, on Tuesday 20 October, according to its official status page. The incident began at 07:00 UK time (08:00 in Spain) and Google declared it over at 13:10, although some virtual machines took longer to recover.

According to Google's preliminary report, published on 22 October, a disturbance on the power grid affected the data centre that hosts the europe-west2-b zone. The facility switched to batteries while the emergency diesel generators started, but the automation systems failed to start them or transfer the load to them. When the batteries ran out, the servers, network and storage in that zone lost power. Moving workloads to neighbouring zones also caused errors and delays in other zones of the region. Google says the root-cause analysis is still ongoing.

That same day, Revolut experienced failures in card payments, transfers, cash withdrawals and account access, according to the Press Association and AFP. In Spain, its status page showed the service as "partially unavailable", according to Selectra. Revolut said its customers' money and data were safe. Halifax acknowledged problems with its app and online banking, and HSBC admitted access "difficulties", according to AFP and PA. The courts service for England and Wales reported an outage of its video platform for remote hearings, according to ITV.

Neither Google nor Revolut has publicly confirmed that Revolut's failures were caused by the Google Cloud outage; AFP attributes that link to a source close to the matter. Google does not name any customers on its status page.

The number of customers affected is not known, nor is the time at which Revolut restored all its services. Google has announced a final report.