Follow these steps to change a disk ID before mapping a thin clone of a cluster volume back to that same cluster. You can also use PowerShell.
- Log in to a stand-alone Windows Server (with or without the Hyper-V role installed) that is available in PowerStore. This server must not be a member of the Hyper-V cluster.
- Open a command window with administrator rights.
- Enter diskpart.
- Enter list disk.
- Note the current list of disks. In this example, Disk 0 is the only disk.
- Use PowerStore Manager to map a thin clone of the cluster disk to this host.
- From the diskpart command prompt, enter rescan.
- Enter list disk.
The new disk (the thin clone) should be listed in an offline state.
- To select the offline disk, enter select disk <#>.
- Enter online disk to bring it online.
- Enter list disk to confirm that the disk is online.
- Enter uniqueid disk to view the current ID for the disk.
- To change the disk ID, enter uniqueid disk ID=<newid>.
- In this example, only the last character of the disk ID is changed to make it unique.
- For an MBR disk, the disk ID is an eight-character string in hexadecimal format.
- For a GPT disk (shown in this example), the disk ID is a longer Globally Unique Identifier (GUID) that is also in hexadecimal format.
Note: If the disk is read-only, an error is returned when attempting to change the disk ID. If this error occurs, enter attributes disk clear readonly to clear the read-only attribute, and repeat this step.
- Enter uniqueid disk again to verify the new ID.
- Now that the thin clone has a new disk signature, exit from diskpart.
- Unmap the disk from the stand-alone host server using PowerStore Manager, and map the disk to the specified Hyper-V cluster.
- Perform a rescan disk on all nodes of the Hyper-V cluster, and bring the disk online. If Windows has automatically assigned a drive letter to any volumes on the disk, remove the drive letters, and return the disk to an offline state.
Note: We recommend disabling automount as a best practice to prevent hosts from automatically assigning drive letters to volumes in Hyper-V recovery scenarios. See Disable automount for details.
- After making changes, put the disk into an offline state, and perform a rescan disk on each node in the Hyper-V cluster. Failure to do a rescan on all Hyper-V nodes will interfere with disk discovery in the next step.
- Add the disk to the Hyper-V cluster. If the original disk was a CSV, convert the disk to a cluster shared volume using the Actions menu in Failover Cluster Manager.
Note: If the cluster is unable to discover the disk, run cluster validation and examine the report for disk errors. After resolving any errors, attempt to add the disk again.
- It might be necessary to clear the cluster reservation attribute on the disk before the disk can be added to Hyper-V. This action can be performed with PowerShell.
- Open a PowerShell window with administrator privileges. Clear the cluster reservation on the disk so that failover cluster manager can discover and import the disk.
- Close PowerShell.
- After the volume is online, perform the required steps, such as data or VM recovery.