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)
|QEMU software virtualization, without KVM
|Linux KVM kernel virtual machine, in combination with QEMU. Not used for other virtualizers using the KVM interfaces, such as Oracle VirtualBox or Amazon EC2 Nitro, see below.
|Amazon EC2 Nitro using Linux KVM
|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
|IBM PowerVM hypervisor — comes as firmware with some IBM POWER servers
|Xen hypervisor (only domU, not dom0)
|Parallels Desktop, Parallels Server
|bhyve, FreeBSD hypervisor
|LMHS SRE hypervisor
|Linux container implementation by LXC
|Linux container implementation by libvirt
|systemd's minimal container implementation, see systemd-nspawn(1)
|Docker container manager
|Podman container manager
|rkt app container runtime
|Windows Subsystem for Linux
|proot userspace chroot/bind mount emulation
|Pouch Container Engine
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.
Detect whether invoked in a confidential virtual machine. The result of this detection may be used to disable features that should not be used in confidential VMs. It must not be used to release security sensitive information. The latter must only be released after attestation of the confidential environment.
Suppress output of the virtualization technology identifier.
Output all currently known and detectable container and VM environments.
Output all currently known and detectable confidential virtualization technologies.
If a virtualization technology is detected, 0 is returned, a non-zero code otherwise.