phpman > man > systemd-machine-id-setup(1)

SYSTEMD-MACHINE-ID-SETUP(1)           systemd-machine-id-setup           SYSTEMD-MACHINE-ID-SETUP(1)



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 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 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.

       --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.

       --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.

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

       -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



systemd 249                                                              SYSTEMD-MACHINE-ID-SETUP(1)