SUMMARY
Some Guest VM disks go offline after a Hyper-V IR has completed.
ISSUE
Purpose
To explain how to resolve an issue where disks are offline for some Windows servers after they are recovered through Hyper-V instant recovery in audit or instant recovery mode.
Description
This problem occurs only when performing a Hyper-V instant recovery. (It does not occur when performing a VM restore.) It affects only Windows server VMs meeting all of the following criteria:
- The servers have multiple SCSi controllers.
- Multiple disks reside on each controller.
- The location number for a disk on one controller is the same as the location number for a disk on another controller.
For example, a Windows server with the following disk configuration would be affected:
- SCSi controller 1 with disks residing in locations 1, 2, and 3.
- SCSi controller 2 with disks residing in locations 1, 4, and 5.
After the recovery, all three disks for SCSi controller 1 would be online, and disks in locations 4 and 5 for controller 2 would also be online. However, the disk in location 1 on controller 2 would be offline.
Resolution
You can resolve this issue by accessing Disk Management on the server VM, right-clicking on the disk in an offline state, and then clicking Online. Procedures may vary slightly depending on the server version.
For more information about Hyper-V instant recovery, see Instant recovery for Hyper-V in the Unitrends Recovery-Series and UEB Adminstrator’s Guide.