# systemd-machine-id-setup

## 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 machine ID is stored in /run/machine-id, the
               machine ID is copied and used to initialize the machine ID in
               /etc/machine-id. This step is skipped if **--root=** is specified
               or running in a chroot environment.
    
            2. 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.
    
            3. If a valid machine ID is provided through **system.machine_id**
               credential, the machine ID is copied and used to initialize
               the machine ID in /etc/machine-id. This step is skipped if
               **--root=** is specified or running in a chroot environment.
    
            4. 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. This step is skipped if **--root=** is specified or
               running in a chroot environment.
    
            5. 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]. This step is skipped if**--root=**
               is specified or running in a chroot environment.
    
            6. 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.
    


## NOTES



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


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