Customers of Microsoft's Azure cloud are reporting capacity issues such as the inability to create resources and associated reliability issues.

Outage-tracking website Down Detector shows quite a few reports about UK Azure issues today, yet the official Azure Status page is all green ticks. The inability to provision resources does not count as an outage as such – though it is more than an annoyance since it is not always feasible to create the resource in an alternative Azure region. Some types of resource have to be same region in order to work correctly without a lot of reconfiguration.

Reports of Azure outages seem mostly connected to capacity issues

Windows Virtual Desktop (WVD), a handy solution for remote workers, is one example. One user complained on Twitter that "Azure seems to be full" when trying to allocate a VM for WVD, though it appears to be a test deployment (if the name WVD-TEST-0 is anything to go by). The error reads "Allocation failed. We do not have sufficient capacity for the requested VM size in this region." The region is UK South.

"Azure appears to be full," said a user attempting a Windows Virtual Desktop deployment

"I can't start any of my VMs that I was using yesterday,” said another customer, and "Azure Functions not triggering reliably," said a third. Although Azure Functions is "serverless" from the user's perspective, it still requires a VM to start up for running the function, so is not immune from capacity issues. Unreliability of existing resources is perhaps a more serious problem than the inability to provision new ones.

Azure status reports all is well

The sudden increase in home working as a consequence of the COVID-19 pandemic means pressure on some cloud services – though you would imagine that use of others will have declined because of temporary business closures. Microsoft has said that, if faced with capacity constraints, "top priority will be going to first responders, health and emergency management services, critical government infrastructure organizational use, and ensuring remote workers stay up and running with the core functionality of Teams."

Is it possible that resource capacity allocated to Teams is affecting customers of other kinds of resource? We have asked Microsoft for any information it can share and will report back.

Note that Azure is a huge service and it would be wrong to give disproportionate weight to a small number of reports. Most of Azure seems to be working fine. That said, capacity in the UK regions was showing signs of stress even before the current crisis, so it is not surprising that issues are occurring now. ®