OVF Packages
Open Virtualization Format (OVF) is a distribution format for virtual applications. vSphere uses the OVF package as a unit of distribution and storage for virtual applications. Because these entities are uploaded, downloaded, and stored in OVF package format, vSphere supports access to and deployment of a wide variety of virtual applications.
A virtual application typically consists of one or more virtual disk files and a configuration file.
- The virtual disk files contain the operating systems and applications that run on the virtual machines in the virtual application.
- The configuration file contains metadata that describes how the virtual application is configured and deployed.
An OVF package might also include certificate and manifest files.
The OVF package contains metadata that describes the capabilities and infrastructure requirements of the virtual application, and contains references to the virtual disks and other files that store the virtual machine state. Most of this information is stored in an XML document called the OVF envelope. When an OVF package is instantiated into either a
VirtualApp
or a VirtualMachine
object (which depends on metadata in the envelope), then the configuration stored in the OVF envelope is applied to the VirtualVApp
and the VirtualMachine
objects.Some of the information in the OVF file is used unaltered, with entire
ovf:Section_Type
elements included in the VirtualApp
object body. Other sections are transformed or extended by instantiation. You do not need detailed knowledge of all OVF package elements, but a basic understanding of key parts of the package and how they relate to virtual applications is useful.See the OVF specification at the DMTF Web site for additional information.