From Wikipedia, the free encyclopedia
Jump to: navigation, search
Virtual Machine Disk Format
VMDK File Format icon.png
Filename extension .vmdk
Developed by VMware
Type of format Disk image file
Website developercenter.vmware.com

VMDK (Virtual Machine Disk) is a file format that describes containers for virtual hard disk drives to be used in virtual machines like VMware Workstation or VirtualBox.

Initially developed by VMware for its virtual appliance products, VMDK is now an open format[1] and is one of the disk formats used in the Open Virtualization Format for virtual appliances.

The maximum VMDK size is generally 2TB for most applications, but in September 2013, VMware vSphere 5.5 introduced 62TB VMDK capacity.[2]


Products that use the VMDK format as the native file format include[edit]

Third-party products with VMDK support include[edit]

  • Parallels Desktop: Version 10 supports VMDK format[3]
  • Sun xVM: natively supports VMDK format[4]
  • QEMU: natively supports VMDK format and provides the qemu-img utility to convert VMDK images to a number of different formats
  • VirtualBox (part of the Oracle VM suite) also supports VMDK files[5]
  • SUSE Studio: builds virtual appliances using the VMDK format, among others
  • Norton GHOST: Hard drive imaging software
  • ILookIX: Computer forensic examination suite
  • Paragon Software Group Hard Disk Manager: P2V migration, backup & restore
  • DiskInternals VMFS Recovery: natively supports VMDK format and recovers data from healthy or corrupted disks

Software libraries with VMDK support include[edit]

Virtual Disk Provisioning Options[edit]

  • thin: Blocks are not allocated or zeroed during initial provisioning. Block allocation and zeroing is performed at first access.
  • zeroedthick: Blocks are allocated during initial provisioning but are not zeroed until first access.
  • eagerzeroedthick: Blocks are allocated and zeroed during initial provisioning.

See also[edit]


  1. ^ "Virtual Disk Format 1.1" (PDF). VMware. 
  2. ^ "vSphere 5.5 Storage Enhancements Part 1: 62TB VMDK". CormacHogan.com. 24 September 2013. Retrieved 11 September 2017. 
  3. ^ "Parallels Announces Parallels Desktop 10 for Mac". www.parallels.com. 
  4. ^ "Oracle and Sun Microsystems - Strategic Acquisitions - Oracle" (PDF). www.sun.com. 
  5. ^ "Chapter 5. Virtual storage". www.virtualbox.org. 

External links[edit]