.\"	$NetBSD: groups.7,v 1.8 2020/04/02 20:57:20 roy Exp $
.\"
.\" SPDX-License-Identifier: BSD-2-Clause
.\"
.\" Copyright (c) 2020 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
.\" POSSIBILITY OF SUCH DAMAGE.
.\"
.Dd April 19, 2026
.Dt GROUPS 7
.Os
.Sh NAME
.Nm groups
.Nd standard group names
.Sh DESCRIPTION
A standard
.Fx
installation has the following user group names:
.Bl -tag -width "realtime"
.It Em wheel
Users authorized to elevate themselves to the super-user privileges of
the root user, meaning uid\~0.
Normally the
.Em wheel
group has gid\~0.
.Pp
Users who are not in the group
.Em wheel
are never allowed by
.Xr su 1
to gain root privileges.
.It Em daemon
Used by the set-group-id programs
.Xr lpr 1
and
.Xr rwho 1 .
.It Em kmem
Used by the set-group-id programs (like
.Xr ktrdump 8 )
that need to access kernel memory
.Po Pa /dev/mem
and
.Pa /dev/kmem
are in the group
.Em kmem
.Pc .
See
.Xr mem 4 .
.It Em sys
Historic group.
Unused in modern
.Fx .
.It Em tty
Used by the set-group-id programs
.Xr wall 1
and
.Xr write 1
to allow users to send messages to another tty even if they don't own
it (static tty device nodes
.Pa /dev/pts/*
are all in the group
.Em tty ) .
See
.Xr tty 4 .
.It Em operator
Users authorized to take backups of disk devices and shut down the
machine.
.Pp
The disk device nodes
(such as
.Pa /dev/ada0 )
are in the group
.Em operator
and group-readable so users in the group can read from disk devices,
for example with
.Xr dump 8 .
The tape device nodes
(such as
.Pa /dev/sa0 )
are in the group
.Em operator
and are both group-readable and group-writable so users in the group
can write to tape devices.
.Pp
The
.Xr shutdown 8
program is executable only by root and members of the
.Em operator
group.
.It Em mail
Used by mail agents (like
.Xr dma 8 ) .
.Pp
By default, root mail
.Pq Pa /var/mail/root
is in the
.Em mail
group.
.It Em bin
Historic group.
Unused in modern
.Fx .
.It Em news
Historic group.
Unused in modern
.Fx .
.It Em man
Historic group; used to be used for managing manual pages (see
.Xr man 1 ) .
.It Em games
Used by various set-group-id games to maintain high-scores files
and other common files in
.Pa /var/games .
The members of this group are also allowed to access
.Pa /dev/input/event*
device nodes (see
.Xr hgame 4 ) .
See also
.Xr intro 6 .
.It Em ftp
Used to be used by
.Xr sysinstall 8
(which is now replaced with
.Xr bsdinstall 8 )
for setting up anonymous FTP.
Unused in modern
.Fx .
.It Em staff
Staff users, in contrast to guest users (see
.Em guest
group).
Not used by
.Fx ;
available for the administrator's interpretation.
See
.Xr security 7
for some recommendations on managing accounts in
.Em staff
group.
.It Em sshd
Primary group for the
.Em sshd
pseudo-user used by the
.Xr sshd 8
secure shell daemon.
.It Em smmsp
Primary group for user
.Em smmsp ,
which is used by
.Xr sendmail 8
if no non-root users were configured for running it.
.Pp
The name of the group means "SendMail Message Submission Program".
.It Em mailnull
Used by electronic mail transport agent
.Xr sendmail 8
as group for its default user
.Em mailnull .
.It Em guest
Guest users, in contrast to staff users (see
.Em staff
group).
Not used by
.Fx ;
available for the administrator's interpretation.
.It Em video
Used for access to
.Pa /dev/drm/*
devices,  which are used for GPU hardware acceleration.
See
.Xr drm 7 .
.It Em realtime
Used by
.Xr mac_priority 4
to allow members of this group to run threads and processes with
realtime scheduling priority.
See also
.Xr rtprio 1 .
.It Em idletime
Used by
.Xr mac_priority 4
to allow members of this group to run processes with idle scheduling
priority.
See also
.Xr idprio 1 .
.It Em bind
Used to be used as primary group for the
.Em bind
pseudo-user used by
.Xr named 8
Internet domain name server, which has been removed from the base system in
.Fx 10.0 .
.It Em unbound
Primary group for the
.Em unbound
pseudo-user used by the
.Xr local-unbound 8
recursive DNS resolver.
.It Em proxy
Primary group for the
.Em proxy
pseudo-user used by the
.Xr ftp-proxy 8
proxy daemon with packet filters such as
.Xr pf 4 .
.It Em authpf
Used by the set-group-id program
.Xr authpf 8
to configure authenticated gateways.
.It Em _pflogd
Primary group for the
.Em _pflogd
pseudo-user used by the
.Xr pflogd 8
log daemon with the
.Xr pf 4
packet filter.
.It Em _dhcp
Primary group for the
.Em _dhcp
pseudo-user used by the
.Xr dhclient 8
DHCP Client.
.It Em dialer
Users authorized to make outgoing modem calls (see
.Xr cu 1
and
.Pa /dev/cuauN
devices).
.It Em network
Historic group.
Unused in modern
.Fx .
.It Em audit
Primary group for the
.Em auditdistd
pseudo-user used by
.Xr auditd 8
and
.Xr auditdistd 8
audit daemons.
.It Em www
Historic group for accessing World Wide Web.
Unused in modern
.Fx .
.It Em u2f
Used for users who need to access
.Pa /dev/u2f/*
devices (see
.Xr u2f 4 ) .
.It Em ntpd
Primary group for the
.Em ntpd
pseudo-user used by the
.Xr ntpd 8
network time protocol daemon.
.It Em _ypldap
Primary group for the
.Em _ypldap
pseudo-user used by
.Xr ypldap 8
daemon.
.It Em hast
Primary group for the
.Em hast
pseudo-user used by
Highly Available Storage daemon
.Xr hastd 8 .
.It Em tests
Primary group for the
.Em tests
pseudo-user used by
automatic tests that request to run unprivileged.
See
.Xr tests 7 .
.It Em nogroup
Pseudo-group (fake group).
It differs from group
.Em nobody
in way that
.Em nogroup
doesn't have a dedicated user for it.
For instance, this group is used for users
.Em tty
and
.Em kmem .
.It Em nobody
Primary group for the traditional
.Em nobody
pseudo-user.
Modern practice is to assign to each different daemon its own separate
pseudo-user account and group so that if one daemon is compromised it
does not compromise all the other daemons.
.Pp
See also group
.Em nogroup .
.El
.Sh FILES
.Bl -tag -width "/usr/src/etc/group" -compact
.It Pa /etc/group
Main group permissions file.
.It Pa /usr/src/etc/group
Group permissions file for the base system.
.It Pa /usr/ports/GIDs
A list of GIDs (group IDs) reserved for ports (see
.Xr ports 7 ) .
.El
.Pp
See
.Xr group 5
for the format of abovementioned files.
.Sh SEE ALSO
.Xr chgrp 1 ,
.Xr groups 1 ,
.Xr id 1 ,
.Xr newgrp 1 ,
.Xr group 5 ,
.Xr pw 8
.Sh HISTORY
The
.Nm
manual page appeared in
.Nx 10.0
and
.Fx 15.1 .