A virtual machine (VM) unexpectedly shuts down when migrated between hosts. Users may also encounter issues taking snapshots of the affected VM, and the VM's disk may show as 0 MB in the vSphere client despite the VM running normally.
- VMware vSphere 6.5 or later
- VMs with non-standard VMDK formats
This issue typically occurs when a VM uses a VMDK file with a non-standard format that is incompatible with standard VMware ESXi operations. The incompatibility often stems from the VMDK being created with atypical parameters, such as an unusual "createType" value in the VMDK descriptor file. The cause of this may be a third-party vendor who doesn't have full access to ESXi, so is using a product such as VMware Workstation to create VMDKs for their customers.
Before attempting to resolve the issue, verify that the problem is indeed caused by an incompatible VMDK format:
Method 1: Using vmkfstools (Recommended for most cases):
Method 2: Using VM-to-VM Conversion:
Method 3: Cloning the VM:
IMPORTANT: Before attempting any of these methods, take a full backup of the VM and, if possible, create a snapshot as an additional precaution. If you're unable to create a snapshot due to the VMDK incompatibility, ensure you have a robust backup before proceeding.
After applying any of these methods, verify that the issue is resolved by attempting to migrate the VM and take a snapshot. The disk size should also now display correctly in the vSphere Client.