Last night, between approximately 21:30 UTC and 22:30 UTC, several Microsoft services, including Azure, Bing, Dynamics, and Xbox Live went down for several users. Users were not able to access the services because of DNS outage. Microsoft observed that its DNS servers saw a spike in DNS traffic. To mitigate the issue, Microsoft engaged resilient DNS capabilities to absorb the spike in DNS traffic.
Microsoft said that it is continuing to investigate to find the root cause and additional preliminary details will be published in the next 24 hours.