What actually happened inside the worldwide IT breakdown?

With so many systems crippled, and companies impacted, the big question is, exactly what went wrong?

Transcript

00:00Yesterday's unprecedented outage boils down to knock-on effects.

00:06They don't call it the web for nothing.

00:08Two systems broke on the same day.

00:10The first was with Microsoft and its cloud service Azure, which has a 25 per cent global

00:16market share.

00:17The second was with CrowdStrike, a cybersecurity provider to almost 18 per cent of the market.

00:23Both crucial, both broken, and both tangled up with the world's tech infrastructure.

00:29Around 7am, Microsoft reported problems with its cloud.

00:34So when all hell broke loose eight hours later, that's where the finger was pointing.

00:38But it looks like the trigger for the real chaos came from CrowdStrike.

00:42A bug in its software update, which was rolled out globally, crashed Windows systems and

00:47everything they touched, dramatically compounding the smaller problems that had been there all

00:52day.

00:53CrowdStrike rolled out a fix yesterday afternoon.

00:57In which case, why are so many systems still down?

01:01The short answer is those knock-on effects.

01:04When a computer crashes, it can cause problems for the computers that rely on it, and the

01:08others that rely on them.

01:10Fixing the first problem helps, but the new problems need their own fix.

01:14A manual reboot, or repair from an IT professional who may or may not have gone home for the

01:20weekend.