Open Virtualization Format (OVF) is an open standard for packaging and distributing virtual machines (VMs) and virtual appliances across virtualization environments. Developed by the Distributed Management Task Force (DMTF), OVF provides a platform-independent method for describing the configuration of virtual environments, facilitating portability, deployment, and integration across various hypervisors and cloud platforms.
The primary goal of OVF is to standardize the packaging of a virtual environment, which includes an operating system, hardware settings, dependencies, licenses, and metadata, for import into virtualization systems. It is widely supported across various ecosystems, including VMware, Microsoft Hyper-V, VirtualBox, and others.
Key Components of an OVF Package
- .ovf file: An XML descriptor that defines the VM’s configuration, including CPU, memory, disk, network settings, and metadata
- Virtual disk files: Files like .vmdk, .vhd, or .qcow2 that contain the operating system and stored data
- .mf file (manifest): Provides file checksums to verify package integrity
- .cert (optional): A certificate used for digitally signing the package
- OVA file (Open Virtual Appliance): A single compressed archive that bundles all OVF components (typically with a .ova extension)
Advantages of Using OVF
- Portability: VMs can be transferred between different virtualization platforms with minimal adjustments
- Automated Deployment: OVF simplifies large-scale deployment of preconfigured applications
- Security: Support for digital signatures and integrity checks
- Simplified Administration: All configuration and image files are bundled together for more straightforward setup
Use Cases
OVF is used to deliver virtual appliances to enterprise customers, deploy test or demo environments, migrate workloads between providers, and create VM templates for cloud marketplaces. It is also relevant in DevOps practices for launching consistent configurations across environments.
As a result, the Open Virtualization Format has become a de facto standard for packaging VMs and distributing complex virtual environments in a platform-agnostic manner.