Libvirt aims to support building and executing on multiple host OS platforms, as well as working with multiple hypervisors. This document outlines which platforms are targeted for each of these areas.
These platforms are used as the basis for deciding upon the minimum required versions of 3rd party software libvirt depends on. If a platform is not listed here, it does not imply that libvirt won't work. If an unlisted platform has comparable software versions to a listed platform, there is every expectation that it will work. Bug reports are welcome for problems encountered on unlisted platforms unless they are clearly older vintage than what is described here.
Note that when considering software versions shipped in distros as support targets, libvirt considers only the version number, and assumes the features in that distro match the upstream release with the same version. In other words, if a distro backports extra features to the software in their distro, libvirt upstream code will not add explicit support for those backports, unless the feature is auto-detectable in a manner that works for the upstream releases too.
The Repology site is a useful resource to identify currently shipped versions of software in various operating systems, though it does not cover all distros listed below.
The project aims to support the most recent major version at all times. Support for the previous major version will be dropped 2 years after the new major version is released or when the vendor itself drops support, whichever comes first. In this context, third-party efforts to extend the lifetime of a distro are not considered, even when they are endorsed by the vendor (e.g. Debian LTS); the same is true of repositories that contain packages backported from later releases (e.g. Debian backports). Within each major release, only the most recent minor release is considered.
For the purposes of identifying supported software versions available on Linux, the project will look at CentOS, Debian, Fedora, openSUSE, RHEL, SLES and Ubuntu LTS. Other distros will be assumed to ship similar software versions.
For FreeBSD, decisions will be made based on the contents of the ports tree; for macOS, Homebrew will be used, although MacPorts is expected to carry similar versions.
For hypervisor drivers which execute locally (QEMU, LXC, VZ, libxl, etc), the set of supported operating system platforms listed above will inform choices as to the minimum required versions of 3rd party libraries and hypervisor management APIs.
If a hypervisor is not commonly shipped directly by any distro listed above, (VMware ESX, HyperV, VZ), the project aims to support versions up to 5 years, or until the vendor discontinues support, whichever comes first.