Microsoft Azure and Office 365 blocked by a DNS configuration error

A DNS CONFIGURATION BLUNDER was blamed for a crash that affected Microsoft Azure and 365 services.

Microsoft cloud users around the world this week complained that they were unable to connect to a multitude of services for several hours due to DNS blocking.

Various Microsoft services have been affected, including Azure databases, Microsoft 365, Teams, Dynamics, OneDrive, SharePoint Online and Compute.

Following fault reports, Microsoft released an update to the Azure status page stating, "Customers may experience intermittent connectivity issues with Azure and other Microsoft services (including M365, Dynamics, DevOps, etc.).

"Engineers are studying DNS resolution issues that affect network connectivity." Connectivity issues have a downstream impact on computing, storage, and database services, and some customers may not be able to submit requests for assistance.

"More information will be provided as soon as it is available.Some customers may start to notice a recovery."

After investigating the outage, Microsoft confirmed that it "might not be possible for users to access the services or features of Microsoft 365," adding that he had "identified and corrected a problem DNS configuration preventing users from accessing the services and features of Microsoft 365 ".

"We have seen an increase in the number of successful connections and our telemetry indicates that all services are being restored and we continue to monitor the environment to confirm that this service has been restored."

The three-hour outage has since ended, with Microsoft confirming that its engineers have alleviated the problem and that most services have been recovered.

"Engineers have identified the underlying root cause as a change of name server delegation affecting DNS resolution and having a downstream impact on computing, storage, application service, and other services. AAD and SQL database, "he said.

"When migrating from a legacy DNS system to Azure DNS, some Microsoft service domains were incorrectly updated. No client DNS records were impacted during this incident, and the Availability of Azure DNS remained 100% throughout the incident.The problem only concerns records for Microsoft services.

To fix this problem, engineers have corrected the name server delegation problem, and applications and services that have accessed the incorrectly configured domains may have cached the incorrect information, resulting in a longer restore time until When their information expires. " μ

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