Multi writer disk expansion failed with error "The virtual disk requires a feature not supported by this program Hot-extend is currently supported only for VMFS flat virtual disks without snapshots opened in persistent mode"
Article ID: 425578
Updated On:
Products
Issue/Introduction
Unable to expand an existing virtual disk on a Virtual Machine. When attempting to increase the size of the disk via the vCenter UI, the operation fails immediately with the following error message:
"The disk extend operation failed. The virtual disk requires a feature not supported by this program, Hot extend is currently supported only for VMFS flat virtual disks without snapshot opened in persistent mode."
Environment
VMware vSphere
Cause
This issue occurs because the virtual disk is configured with the Multi-Writer attribute and is currently attached to one or more Virtual Machines that are powered on.
VMware vSphere does not support Hot Extend (online expansion) for virtual disks with the Multi-Writer flag enabled. The hypervisor cannot safely resize the underlying VMDK while multiple VMs hold active write locks on the file, as this risks data corruption and metadata conflicts.
Resolution
To successfully expand a Multi-Writer enabled VMDK, the disk must be resized in an offline state (Cold Extend). Follow the steps below:
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Identify Associated VMs: Locate all Virtual Machines that are currently sharing/attached to the specific Multi-Writer disk.
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Power Off: Shut down all identified Virtual Machines. (The disk cannot be expanded if even one attached VM is still running).
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Expand Disk: Once all VMs are confirmed powered off, navigate to the disk settings in the vCenter UI and perform the disk expansion (increase the provisioned size).
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Power On: Power the Virtual Machines back on.
Additional Information
To understand the supported operations with Multi writer disks refer to article - Enabling or disabling simultaneous write protection provided by VMFS using the multi-writer flag
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