Google Cloud’s London Outage Shows Why Cloud Resilience Must Be Tested

A six-hour Google Cloud disruption in London on 20 October shows why hosting a service in the cloud does not, by itself, guarantee that the service will stay available. Google’s preliminary report traces the incident from a power interruption at one availability zone to wider delays across regional services. The lesson for Pakistani organisations is to test how critical systems behave when a cloud zone or provider dependency fails.

Google’s service-health report says multiple services in its London-based europe-west2 region were disrupted for six hours and ten minutes on 20 October. The physical outage affected the europe-west2-b availability zone. Google lists services including Compute Engine, Google Kubernetes Engine, Cloud SQL, BigQuery and Cloud Run among those affected.

How a single-zone failure spread

Google’s preliminary account says a power interruption occurred at the facility hosting the affected zone. The site’s uninterruptible power supplies initially carried the load, but a fault in the automatic generator-start sequence meant backup generators did not take over before battery reserves ran down. Hosts, network equipment and local storage in that zone went offline. Google says its engineering teams isolated the zone and gradually restored services.

The impact did not stop neatly at the zone boundary. Traffic moved toward other zones, but the sudden demand and dependencies on components in the unavailable zone created queues, timeouts and errors elsewhere in the region. Google’s report says some customers whose workloads were in other zones or used regional architectures also experienced problems. The report is labelled preliminary, so its root-cause details may change as Google completes its investigation.

Reuters reported disruption to several UK financial and public-facing services. Digital bank Revolut said some card-payment and ATM functions were affected, while it told Reuters that customer money and data remained safe. The UK Financial Conduct Authority said it was engaging with Google and affected firms. These reports describe UK services; they do not establish that Pakistani customers or systems were affected.

What this means for Pakistan-based teams

The practical relevance is conditional. A Pakistani company that hosts a website, database or application in Google’s London region—or depends on a supplier whose system is there—could face impact during a similar regional incident. Teams should check where each critical service actually runs, including databases, authentication, payment connections and third-party APIs. A provider’s global brand is not a substitute for knowing the workload’s location and dependencies.

Google’s documentation describes a zone as a failure domain and says deploying across multiple zones can help protect against unexpected failures. But the October incident shows that a zone outage can still create pressure on regional control systems and remaining capacity. For protection against a region-wide failure, Google says customers must design, build and test recovery between regions themselves; replication or a second region is not automatically configured for every product.

Start with recovery goals, not a multi-cloud slogan. Decide how much data the organisation can afford to lose and how long each essential service can remain unavailable. Those targets guide backup frequency, replication and failover choices. Then run a recovery exercise: restore a backup, bring up the standby service, redirect traffic and confirm staff can communicate with customers. Google’s disaster-recovery guidance explicitly recommends testing recovery regularly.

Small businesses do not always need a second live region for every tool. They do need to identify their most important user journeys, know the single-zone and single-provider dependencies, and write down a workable response if a supplier is unavailable. If a website can show a service notice while payment or inventory systems recover, that is better than an unexplained failure. Retries and timeouts should also be configured so a surge of repeated requests does not worsen an outage.

Regulated firms need a documented plan

In Pakistan, the State Bank of Pakistan’s Framework on Outsourcing to Cloud Service Providers sets minimum, risk-based requirements for regulated financial entities that outsource workloads to cloud providers. The Google event does not imply a breach of that framework or an outage at a Pakistani bank. It is a reminder for regulated organisations to review their own cloud risk assessments, provider dependencies and recovery arrangements under the rules that apply to them.

Cloud platforms can reduce the burden of running physical infrastructure, but resilience still depends on architecture, configuration and rehearsed recovery. For teams in Chitral, elsewhere in Pakistan or abroad, the useful question is not simply “Are we on the cloud?” It is “What will our customers see if one zone, one region or one essential supplier goes offline—and have we practised the answer?”

Sources

• Google Cloud Service Health — Incident report for europe-west2
• Reuters — Google Cloud outage disrupts UK services
• The Register — Google Cloud says a power event caused the outage
• Google Cloud documentation — Consider geographic distribution
• Google Cloud documentation — Disaster recovery
• State Bank of Pakistan — Framework on Outsourcing to Cloud Service Providers