Open Virtualization Format (OVF) is an open-source standard for packaging and distributing virtual machines (VM) and it is platform independent.. You can watch/consider OVF as a container or a package which contains OVF descriptor. This container/package can be used to port any VMs to any vendor specific virt setups which support OVF. OVF is basically a XML format which have information about VM’s disks, virtual hardware resources..etc
OVF descriptor mainly has below details with it :
ProductSection, which provides product information such as name and vendor of the appliance
and a set of properties that can be used to customize the appliance. These properties will be
configured at installation time of the appliance, typically by prompting the user.
AnnotationSection, which is a free form annotation.
EulaSection, the licensing terms for the appliance. This is typically shown during install.
HardwareSection, which describes the virtual hardware. This is a required section that describes the kind of virtual hardware and set of devices that the virtual machine requires. In this particular case, a fairly typical set of hardware (500 MB of guest memory, 1 CPU, 1 NIC, and one virtual
disk) is specified. The network and disk identifiers from the outer sections are referenced here.
OperatingSystemSection, which describes the guest operating system.
Above tool can be used to migrate/port older vm formats to OVF formats.
Refer # www.linux-mag.com/id/7389/
More details can be fetched from :
www.dmtf.org/standards/published_documents/DSP0243_1.1.0.pdf ( OVF specification)
www.dmtf.org/standards/published_documents/DSP2017_1.0.0.pdf (OVF whitepaper)