− Initialize the machine ID in
may be used by system installer tools to initialize the
machine ID stored in /etc/machine−id at install time,
with a provisioned or randomly generated ID. See
machine-id(5) for more information about this
If the tool is
invoked without the −−commit switch,
/etc/machine−id is initialized with a valid, new
machined ID if it is missing or empty. The new machine ID
will be acquired in the following fashion:
1. If a valid
D−Bus machine ID is already configured for the system,
the D−Bus machine ID is copied and used to initialize
the machine ID in /etc/machine−id.
2. If run
inside a KVM virtual machine and a UUID is was configured
(via the −uuid option), this UUID is used to
initialize the machine ID. The caller must ensure that the
UUID passed is sufficiently unique and is different for
every booted instance of the VM.
if run inside a Linux container environment and a UUID is
configured for the container, this is used to initialize the
machine ID. For details, see the documentation of the
Otherwise, a new ID is randomly generated.
−−commit switch may be used to commit a
transient machined ID to disk, making it persistent. For
details, see below.
systemd-firstboot(1) to initialize the machine ID on
mounted (but not booted) system images.
following options are understood:
directory path as argument. All paths operated will be
prefixed with the given alternate root path,
including the path for /etc/machine−id
transient machine ID to disk. This command may be used to
convert a transient machine ID into a persistent one. A
transient machine ID file is one that was bind mounted from
a memory file system (usually "tmpfs") to
/etc/machine−id during the early phase of the boot
process. This may happen because /etc is initially
read−only and was missing a valid machine ID file at
command will execute no operation if /etc/machine−id
is not mounted from a memory file system, or if /etc is
read−only. The command will write the current
transient machine ID to disk and unmount the
/etc/machine−id mount point in a race−free
manner to ensure that this file is always valid and
accessible for other processes.
command is primarily used by the
systemd-machine-id-commit.service(8) early boot
short help text and exit.
short version string and exit.
success, 0 is returned, a non−zero failure code