Microsoft 364 trips over its own network settings in North America

Outage blamed on misconfigured infrastructure as users report hour-long disruption

Microsoft 365 services toppled over in North America last night due to an infrastructure misconfiguration.

According to affected users, the outage started at 1810 UTC on October 9 and affected all Microsoft 365 services including Teams. The outage was brief, and just over an hour later, Microsoft confirmed that everything was back to normal.

The blackout came shortly after another in which Microsoft blamed a Kubernetes crash for taking down a substantial chunk of Azure Front Door instances. Microsoft said it had "ruled out any deployments that could have triggered this event."

Of the latest wobble, Microsoft said: "We identified that a portion of network infrastructure in North America was misconfigured, resulting in impact."

Several users attributed the problems to the AT&T network, although neither Microsoft nor the telco have confirmed this. Other users reported that switching to a backup circuit restored services.

The Register contacted both companies and will update the article should we receive a response.

The downtime highlights the potential brittleness of cloud infrastructure and the risks introduced by configuration changes. Microsoft did not detail the misconfiguration, but administrators left with suddenly disconnected users might question whether putting all their eggs in a cloudy basket was wise – especially when a single error can knock out services and rerouting takes time to restore them.

Regarding the debacle in North America, Microsoft stated that it had "rerouted the impacted traffic to healthy infrastructure" before eventually confirming the issue as resolved.

The company's Admin Center said: "We're analyzing configuration policies and traffic management processes on the affected network infrastructure to identify necessary refinements and increase resilience in the event of future incidents."

It did not call out any particular network provider in its updates. ®