How to Migrate (storage vmotion) datastore containing a clustered disk to another separate array.

Products

• VMware vCenter Server
• VMware vSphere ESXi

Issue/Introduction

A datastore contains a disk that is shared between two windows servers. This utilizes the "clustered disk" configuration within windows.
What are the proper steps to storage vmotion everything on the current datastore (containing the clustered disk) to another separate array?

 

 

Environment

vCenter Server 7.x
vCenter Server 8.x

Cause

N/A

Resolution

To migrate a clustered Windows disk on ESXi to a new, separate storage array, you need to perform a "Storage vMotion" operation within the vSphere client, essentially moving the virtual disk associated with the clustered Windows volume to the new datastore presented by the separate array, while keeping the virtual machine running; helps ensure to properly manage the cluster configuration on the Windows side to maintain failover functionality throughout the migration process. 

NOTE:  vSphere does not permit Storage vMotion when a virtual machine is using SCSI bus-sharing, or vMotion when a virtual machine is using virtual SCSI bus-sharing. To work around this issue, VMware recommends migrating such a virtual machine by powering it down first and then performing a cold migration to the new host and/or datastore(s).

Cold migrations of disks configured with bus-sharing require all virtual machines using those disks, such as other WSFC nodes, be powered off. After migrating, ensure that all other virtual machines that were using the migrated disks are updated with the new shared disk locations, otherwise they will fail to power on.

Here are the steps involved:

Prepare the new storage array:
Add the new storage array to your ESXi hosts and make the datastores accessible. 
Verify the new datastore has sufficient space for the clustered disk.

Backup the cluster configuration:
Before any changes, create a backup of your Windows Server Failover Cluster (WSFC) configuration to ensure you can restore if needed. 

Access the vSphere client:
Log in to your vCenter server and navigate to the virtual machine associated with the clustered disk. 

Initiate Storage vMotion:

• Right-click on the virtual machine and select "Migrate". 
• Choose "Change storage only". 
• Select the new datastore on the separate array as the destination.
• Review the migration details and click "Finish". 

Important considerations:

Cluster ownership:
Ensure that before migrating, the cluster disk ownership is on a single node to avoid conflicts during the process. 

Failover management:
During the migration, consider temporarily taking the cluster resource offline to minimize disruption. 
Once the disk migration is complete, update the cluster configuration on the Windows side to reflect the new storage location. 

Network bandwidth:
If the clustered disk is large, ensure adequate network bandwidth to support the data transfer during the migration. 

SCSI controller settings:
Verify that the SCSI controller settings for the virtual disk remain consistent after the migration.