noble (1) systemd-machine-id-setup.1.gz

Provided by: systemd_255.4-1ubuntu8.5_amd64 bug

NAME

       systemd-machine-id-setup - Initialize the machine ID in /etc/machine-id

SYNOPSIS

       systemd-machine-id-setup

DESCRIPTION

       systemd-machine-id-setup 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 file.

       If the tool is invoked without the --commit switch, /etc/machine-id is initialized with a valid, new
       machine 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 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.

        3. Similarly, 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 Container
           Interface[1].

        4. Otherwise, a new ID is randomly generated.

       The --commit switch may be used to commit a transient machined ID to disk, making it persistent. For
       details, see below.

       Use systemd-firstboot(1) to initialize the machine ID on mounted (but not booted) system images.

OPTIONS

       The following options are understood:

       --root=path
           Takes a directory path as argument. All paths operated on will be prefixed with the given alternate
           root path, including the path for /etc/machine-id itself.

           Added in version 212.

       --image=path
           Takes a path to a device node or regular file as argument. This is similar to --root= as described
           above, but operates on a disk image instead of a directory tree.

           Added in version 249.

       --image-policy=policy
           Takes an image policy string as argument, as per systemd.image-policy(7). The policy is enforced when
           operating on the disk image specified via --image=, see above. If not specified defaults to the "*"
           policy, i.e. all recognized file systems in the image are used.

       --commit
           Commit a 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 that point.

           This 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.

           This command is primarily used by the systemd-machine-id-commit.service(8) early boot service.

           Added in version 227.

       --print
           Print the machine ID generated or committed after the operation is complete.

           Added in version 231.

       -h, --help
           Print a short help text and exit.

       --version
           Print a short version string and exit.

EXIT STATUS

       On success, 0 is returned, a non-zero failure code otherwise.

SEE ALSO

       systemd(1), machine-id(5), systemd-machine-id-commit.service(8), dbus-uuidgen(1), systemd-firstboot(1)

NOTES

        1. Container Interface
           https://systemd.io/CONTAINER_INTERFACE