Product Documentation

VHDX chain of differencing disks

Mar 08, 2017

Versioning simplifies vDisk update and management tasks, providing a more flexible and robust approach to managing vDisks.

A vDisk consists of a VHDX base image file, any associated side-car files, and if applicable, a chain of referenced VHDX differencing disks. Differencing disks are created to capture the changes made to the base disk image, leaving the original base disk unchanged. Each differencing disk that is associated with a base disk represents a different version.

The following illustrates the file naming convention used and the relationship between a a base disk and all versions referencing that base disk.

VHDX Chain

Note: vDisk versions are created and managed using the vDisk Versions dialog and by performing common vDisk versioning tasks.
Each time a vDisk is put into Maintenance Mode a new version of the VHDX differencing disk is created and the file name is numerically incremented, as captured in the table that follows.
  VHDX Filename Properties Filename Lock File Filename
Base Image win7dev.vhdx win7dev.pvp win7dev.lok
Version 1 win7dev.1.vhdx win7dev.1.pvp win7dev.1.lok
Version 2 win7dev.2.vhdx win7dev.2.pvp win7dev.2.lok
... ... ... ...
Version N win7dev.N.vhdx win7dev.N.pvp win7dev.N.lok

For information on merging VHDX files, refer to merging VHDX files.