systemd-sysusers, systemd-sysusers.service — Allocate system users and groups
systemd-sysusers [OPTIONS...] [
systemd-sysusers creates system users and groups, based on files in the format described in sysusers.d(5).
If invoked with no arguments, it applies all directives from all files found in the directories
invoked with positional arguments, if option
is specified, arguments specified on the command line are used instead of the configuration file
PATH. Otherwise, just the configuration specified by the command line
arguments is executed. The string "
-" may be specified instead of a filename to instruct
systemd-sysusers to read the configuration from standard input. If the argument is a
relative path, all configuration directories are searched for a matching file and the file found that has
the highest priority is executed. If the argument is an absolute path, that file is used directly without
searching of the configuration directories.
The following options are understood:
Takes a directory path as an argument. All
paths will be prefixed with the given alternate
root path, including config search
Takes a path to a disk image file or block device node. If specified all operations
are applied to file system in the indicated disk image. This is similar to
but operates on file systems stored in disk images or block devices. The disk image should either
contain just a file system or a set of file systems within a GPT partition table, following the
Specification. For further information on supported disk images, see
switch of the same name.
When this option is given, one or more positional arguments
must be specified. All configuration files found in the directories listed in
will be read, and the configuration given on the command line will be
handled instead of and with the same priority as the configuration file
This option is intended to be used when package installation scripts are running and files belonging to that package are not yet available on disk, so their contents must be given on the command line, but the admin configuration might already exist and should be given higher priority.
Example 1. RPM installation script for radvd
echo 'u radvd - "radvd daemon"' | \ systemd-sysusers --replace=/usr/lib/sysusers.d/radvd.conf -
This will create the radvd user as if
/usr/lib/sysusers.d/radvd.conf was already on disk.
An admin might override the configuration specified on the command line by
/etc/sysusers.d/radvd.conf or even
Note that this is the expanded form, and when used in a package, this would be written using a macro with "radvd" and a file containing the configuration line as arguments.
Process the configuration and figure out what entries would be created, but don't actually write anything.
Treat each positional argument as a separate configuration line instead of a file name.
Copy the contents of config files to standard output. Before each file, the filename is printed as a comment.
Do not pipe output into a pager.
systemd-sysusers supports the service credentials logic as implemented by
details). The following credentials are used when passed in:
A UNIX hashed password string to use for the specified user, when creating an entry
for it. This is particularly useful for the "
root" user as it allows provisioning
the default root password to use via a unit file drop-in or from a container manager passing in this
credential. Note that setting this credential has no effect if the specified user account already
exists. This credential is hence primarily useful in first boot scenarios or systems that are fully
stateless and come up with an empty
/etc/ on every boot.
Similar to "
but expect a literal, plaintext password, which is then automatically hashed before used for the user
account. If both the hashed and the plaintext credential are specified for the same user the
former takes precedence. It's generally recommended to specify the hashed version; however in test
environments with weaker requirements on security it might be easier to pass passwords in plaintext
Specifies the shell binary to use for the specified account when creating it.
The contents of this credential may contain additional lines to operate on. The
credential contents should follow the same format as any other
drop-in. If this credential is passed it is processed after all of the drop-in files read from the
Note that by default the
systemd-sysusers.service unit file is set up to
inherit the "
sysusers.extra" credentials from the service manager. Thus, when invoking a container
with an unpopulated
/etc/ for the first time it is possible to configure the root
user's password to be "
systemd" like this:
# systemd-nspawn --image=… --set-credential=passwd.hashed-password.root:'$y$j9T$yAuRJu1o5HioZAGDYPU5d.$F64ni6J2y2nNQve90M/p0ZP0ECP/qqzipNyaY9fjGpC' …
Note again that the data specified in this credential is consulted only when creating an account for the first time, it may not be used for changing the password or shell of an account that already exists.
Use mkpasswd(1) for generating UNIX password hashes from the command line.
On success, 0 is returned, a non-zero failure code otherwise.