mirror of
https://github.com/systemd/systemd.git
synced 2024-12-22 17:35:35 +03:00
55 lines
2.6 KiB
Markdown
55 lines
2.6 KiB
Markdown
---
|
|
title: VM Interface
|
|
category: Interfaces
|
|
layout: default
|
|
SPDX-License-Identifier: LGPL-2.1-or-later
|
|
---
|
|
|
|
# The VM Interface
|
|
|
|
Also consult [Writing Virtual Machine or Container
|
|
Managers](https://systemd.io/WRITING_VM_AND_CONTAINER_MANAGERS).
|
|
|
|
systemd has a number of interfaces for interacting with virtual machine
|
|
managers, when systemd is used inside of a VM. If you work on a VM manager,
|
|
please consider supporting the following interfaces.
|
|
|
|
1. systemd supports passing immutable binary data blobs with limited size and
|
|
restricted access to services via the `ImportCredential=`, `LoadCredential=`
|
|
and `SetCredential=` settings. These credentials may be passed into a system
|
|
via SMBIOS Type 11 vendor strings, see
|
|
[systemd(1)](https://www.freedesktop.org/software/systemd/man/latest/systemd.html)
|
|
for details. This concept may be used to flexibly configure various facets
|
|
ot the guest system. See
|
|
[systemd.system-credentials(7)](https://www.freedesktop.org/software/systemd/man/latest/systemd.system-credentials.html)
|
|
for a list of system credentials implemented by various systemd components.
|
|
|
|
2. Readiness, information about various system properties and functionality, as
|
|
well as progress of boot may be reported by systemd to a machine manager via
|
|
the `sd_notify()` protocol via `AF_VSOCK` sockets. The address of this
|
|
socket may be configured via the `vmm.notify_socket` system credential. See
|
|
[systemd(1)](https://www.freedesktop.org/software/systemd/man/latest/systemd.html).
|
|
|
|
3. The
|
|
[systemd-ssh-generator(8)](https://www.freedesktop.org/software/systemd/man/latest/systemd-ssh-generator.html)
|
|
functionality will automatically bind SSH login functionality to `AF_VSOCK`
|
|
port 22, if the system runs in a VM.
|
|
|
|
4. If not initialized yet the system's
|
|
[machine-id(5)](https://www.freedesktop.org/software/systemd/man/latest/machine-id.html)
|
|
is automatically set to the SMBIOS product UUID if available and invocation
|
|
in an VM environment is detected.
|
|
|
|
5. The
|
|
[`systemd-boot(7)`](https://www.freedesktop.org/software/systemd/man/latest/systemd-boot.html)
|
|
and
|
|
[`systemd-stub(7)`](https://www.freedesktop.org/software/systemd/man/latest/systemd-stub.html)
|
|
components support two SMBIOS Type 11 vendor strings that may be used to
|
|
extend the kernel command line of booted Linux environments:
|
|
`io.systemd.stub.kernel-cmdline-extra=` and
|
|
`io.systemd.boot.kernel-cmdline-extra=`.
|
|
|
|
Also see
|
|
[smbios-type-11(7)](https://www.freedesktop.org/software/systemd/man/latest/smbios-type-11.html)
|
|
for a list of supported SMBIOS Type 11 vendor strings.
|