Linked Virtual Machines Linked virtual machines are two or more virtual machines that share storage and support efficient sharing of duplicated data. Linked Virtual Machines and Disk BackingsIn its simplest form, shared storage is achieved through the use of delta disk backings. A delta disk backing is a virtual disk file that sits on top of a standard virtual disk backing file. Each time the guest operating system on a virtual machine writes to disk, the data is written to the delta disk. Each time the guest operating system on a virtual machine reads from disk, the virtual machine first targets the disk block in the delta disk. If the data is not on the delta disk, the virtual machine looks for it on the base disk. Creating a Linked Virtual MachineYou can create linked virtual machines in one of two ways:Instant Clone Virtual MachinesThe instant clone operation creates a running virtual machine that continues running from the current state of the source virtual machine. There is no delay to power on the cloned virtual machine. Removing Snapshots and Deleting Linked Virtual MachinesAfter you have created a group of linked virtual machines, you can remove a snapshot that was the basis for a linked virtual machine, or delete a virtual machine. Those actions affect disks in the linked virtual machine group. Perform the actions when connected to a vCenter Server system for disk consolidation or deletion. Relocating a Virtual Machine in a Linked Virtual Machine GroupYou can move the virtual machines in a linked virtual machine group between datastores and save storage. he contents of the delta disk might not be as important as the contents of the base, and you can save storage by removing the delta disk. Promoting a Virtual Machine's DiskPromoting a virtual machine’s disk improves performance.Performing Advanced Manipulation of Delta DisksFor advanced manipulation of delta disks, you can use VirtualDeviceConfigSpec methods such as VirtualDeviceConfigSpec.create and VirtualDeviceConfigSpec.add. Parent topic: Virtual Machine Management