Today, Microsoft only supports a single Microsoft Azure Stack region and that Azure Stack region supports a single Microsoft Azure Stack scale unit. Currently, a scale unit is synonymous with a rack and consists of a minimum of four scale unit nodes and a maximum of 16 scale unit nodes, an HLH, two top-of-rack switches, one baseboard management controller (BMC) switch, power distribution units, and a rack. This exposes your Microsoft Azure Stack appliance to the risk of catastrophic events at your data center or failures due to hardware, operational, or product issues.

If such a disaster strikes, your Microsoft Azure Stack appliance goes offline. At that point, all of the data is potentially unrecoverable. Depending on the root cause analysis of your data loss, you may need to repair an infrastructure service with guidance from Microsoft Product Support, for example, Network Controller, or restore the entire Microsoft Azure Stack appliance.