systemd-detect-virt — Detect execution in a virtualized environment
systemd-detect-virt detects execution in
a virtualized environment. It identifies the virtualization
technology and can distinguish full machine virtualization from
exits with a return value of 0 (success) if a virtualization
technology is detected, and non-zero (error) otherwise. By default,
any type of virtualization is detected, and the options
--vm can be used
to limit what types of virtualization are detected.
When executed without
--quiet will print a
short identifier for the detected virtualization technology. The
following technologies are currently identified:
Table 1. Known virtualization technologies (both VM, i.e. full hardware virtualization, and container, i.e. shared kernel virtualization)
|VM||QEMU software virtualization, without KVM|
|Linux KVM kernel virtual machine, with whatever software, except Oracle Virtualbox|
|VMware Workstation or Server, and related products|
|Hyper-V, also known as Viridian or Windows Server Virtualization|
|Oracle VM VirtualBox (historically marketed by innotek and Sun Microsystems), for legacy and KVM hypervisor|
|Xen hypervisor (only domU, not dom0)|
|Parallels Desktop, Parallels Server|
|bhyve, FreeBSD hypervisor|
|Linux container implementation by LXC|
|Linux container implementation by libvirt|
|systemd's minimal container implementation, see systemd-nspawn(1)|
|Docker container manager|
|rkt app container runtime|
|Windows Subsystem for Linux|
If multiple virtualization solutions are used, only the
"innermost" is detected and identified. That means if both
machine and container virtualization are used in
conjunction, only the latter will be identified (unless
--vm is passed).
Windows Subsystem for Linux is not a Linux container, but an environment for running Linux userspace applications on top of the Windows kernel using a Linux-compatible interface. WSL is categorized as a container for practical purposes. Multiple WSL environments share the same kernel and services should generally behave like when being run in a container.
The following options are understood:
Only detects container virtualization (i.e. shared kernel virtualization).
Only detects hardware virtualization.
Detect whether invoked in a
environment. In this mode, no output is written, but the return
value indicates whether the process was invoked in a
environment or not.
Detect whether invoked in a user namespace. In this mode, no output is written, but the return value indicates whether the process was invoked inside of a user namespace or not. See user_namespaces(7) for more information.
Suppress output of the virtualization technology identifier.
Output all currently known and detectable container and VM environments.
If a virtualization technology is detected, 0 is returned, a non-zero code otherwise.