'\" t .TH "SYSUSERS\&.D" "5" "" "systemd 215" "sysusers.d" .\" ----------------------------------------------------------------- .\" * Define some portability stuff .\" ----------------------------------------------------------------- .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .\" http://bugs.debian.org/507673 .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" ----------------------------------------------------------------- .\" * set default formatting .\" ----------------------------------------------------------------- .\" disable hyphenation .nh .\" disable justification (adjust text to left margin only) .ad l .\" ----------------------------------------------------------------- .\" * MAIN CONTENT STARTS HERE * .\" ----------------------------------------------------------------- .SH "NAME" sysusers.d \- Declarative allocation of system users and groups .SH "SYNOPSIS" .PP /usr/lib/sysusers\&.d/*\&.conf .SH "DESCRIPTION" .PP \fBsystemd\-sysusers\fR uses the files from sysusers\&.d directory to create system users and groups at package installation or boot time\&. This tool may be used to allocate system users and groups only, it is not useful for creating non\-system users and groups, as it accesses /etc/passwd and /etc/group directly, bypassing any more complex user databases, for example any database involving NIS or LDAP\&. .SH "CONFIGURATION FORMAT" .PP Each configuration file shall be named in the style of \fIpackage\fR\&.conf or \fIpackage\fR\-\fIpart\fR\&.conf\&. The second variant should be used when it is desirable to make it easy to override just this part of configuration\&. .PP The file format is one line per user or group containing name, ID and GECOS field description: .sp .if n \{\ .RS 4 .\} .nf # Type Name ID GECOS u httpd 440 "HTTP User" u authd /usr/bin/authd "Authorization user" g input \- \- m authd input .fi .if n \{\ .RE .\} .SS "Type" .PP The type consists of a single letter\&. The following line types are understood: .PP \fIu\fR .RS 4 Create a system user and group of the specified name should they not exist yet\&. The user\*(Aqs primary group will be set to the group bearing the same name\&. The user\*(Aqs shell will be set to /sbin/nologin, the home directory to /\&. The account will be created disabled, so that logins are not allowed\&. .RE .PP \fIg\fR .RS 4 Create a system group of the specified name should it not exist yet\&. Note that \fIu\fR implicitly create a matching group\&. The group will be created with no password set\&. .RE .PP \fIm\fR .RS 4 Add a user to a group\&. If the user or group are not existing yet, they will be implicitly created\&. .RE .SS "Name" .PP The name field specifies the user or group name\&. It should be be shorter than 31 characters and avoid any non\-ASCII characters, and not begin with a numeric character\&. It is strongly recommended to pick user and group names that are unlikely to clash with normal users created by the administrator\&. A good scheme to guarantee this is by prefixing all system and group names with the underscore, and avoiding too generic names\&. .PP For \fIm\fR lines this field should contain the user name to add to a group\&. .SS "ID" .PP For \fIu\fR and \fIg\fR the numeric 32bit UID or GID of the user/group\&. Do not use IDs 65535 or 4294967295, as they have special placeholder meanings\&. Specify "\-" for automatic UID/GID allocation for the user or group\&. Alternatively, specify an absolute path in the file system\&. In this case the UID/GID is read from the path\*(Aqs owner/group\&. This is useful to create users whose UID/GID match the owners of pre\-existing files (such as SUID or SGID binaries)\&. .PP For \fIm\fR lines this field should contain the group name to add to a user to\&. .SS "GECOS" .PP A short, descriptive string for users to be created, enclosed in quotation marks\&. Note that this field may not contain colons\&. .PP Only applies to lines of type \fIu\fR and should otherwise be left unset\&. .SH "OVERRIDING VENDOR CONFIGURATION" .PP Note that \fBsystemd\-sysusers\fR will do nothing if the specified users or groups already exist, so normally there no reason to override sysusers\&.d vendor configuration, except to block certain users or groups from being created\&. .PP Files in /etc/sysusers\&.d override files with the same name in /usr/lib/sysusers\&.d and /run/sysusers\&.d\&. Files in /run/sysusers\&.d override files with the same name in /usr/lib/sysusers\&.d\&. The scheme is the same as for \fBtmpfiles.d\fR(5), except for the directory name\&. .PP If the administrator wants to disable a configuration file supplied by the vendor, the recommended way is to place a symlink to /dev/null in /etc/sysusers\&.d/ bearing the same filename\&. .SH "SEE ALSO" .PP \fBsystemd\fR(1), \fBsystemd-sysusers\fR(8), \fBtmpfiles.d\fR(5)