Attack on Microsoft Azure network blamed for cloud-computing slowness

In this photo illustration, the American file hosting and cloud computing service owned by Microsoft, Azure logo is seen displayed on a smartphone with an economic stock exchange index graph in the background. (Photo Illustration by Budrul Chukrut/SO

Microsoft says its Azure cloud computing servers were hit by a distributed denial-of-service (DDoS) attack on Tuesday, causing connection problems for users around the world.

"We're currently investigating access issues and degraded performance with multiple Microsoft 365 services and features," the company tweeted Tuesday morning.

Some users were reporting problems and even outages of cloud-based services like its Microsoft 365 administrative tools, as well as the web-based version Outlook email.

The company's Azure status board showed network infrastructure warnings across the world just after 9 a.m. ET, though none were marked as "critical."

By late afternoon, the company said it had determined that the "initial trigger event" was a DDoS attack – when a bad actor floods a system with traffic in an attempt to overload it – but some of the company's attempts to fight off the attack inadvertently made things worse.

Microsoft said all services were restored just before 5 p.m. ET.

The issue came days after software update by CrowdStrike, a security firm, led to a global outage of some Microsoft systems. Delta Airlines and several other major businesses were knocked offline.

What is Microsoft Azure?

Azure is the name of Microsoft's cloud-computing platform. It allows individuals, companies, and governments to access services across the internet ranging from data management to communication to multimedia delivery.

Similar services are available through competitors like Google Cloud and Amazon Web Services.