xref: /freebsd/share/man/man7/groups.7 (revision d5db883af2cc46bf884ba3fd067cec68f44fc66d)
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29.Dd April 19, 2026
30.Dt GROUPS 7
31.Os
32.Sh NAME
33.Nm groups
34.Nd standard group names
35.Sh DESCRIPTION
36A standard
37.Fx
38installation has the following user group names:
39.Bl -tag -width "realtime"
40.It Em wheel
41Users authorized to elevate themselves to the super-user privileges of
42the root user, meaning uid\~0.
43Normally the
44.Em wheel
45group has gid\~0.
46.Pp
47Users who are not in the group
48.Em wheel
49are never allowed by
50.Xr su 1
51to gain root privileges.
52.It Em daemon
53Used by the set-group-id programs
54.Xr lpr 1
55and
56.Xr rwho 1 .
57.It Em kmem
58Used by the set-group-id programs (like
59.Xr ktrdump 8 )
60that need to access kernel memory
61.Po Pa /dev/mem
62and
63.Pa /dev/kmem
64are in the group
65.Em kmem
66.Pc .
67See
68.Xr mem 4 .
69.It Em sys
70Historic group.
71Unused in modern
72.Fx .
73.It Em tty
74Used by the set-group-id programs
75.Xr wall 1
76and
77.Xr write 1
78to allow users to send messages to another tty even if they don't own
79it (static tty device nodes
80.Pa /dev/pts/*
81are all in the group
82.Em tty ) .
83See
84.Xr tty 4 .
85.It Em operator
86Users authorized to take backups of disk devices and shut down the
87machine.
88.Pp
89The disk device nodes
90(such as
91.Pa /dev/ada0 )
92are in the group
93.Em operator
94and group-readable so users in the group can read from disk devices,
95for example with
96.Xr dump 8 .
97The tape device nodes
98(such as
99.Pa /dev/sa0 )
100are in the group
101.Em operator
102and are both group-readable and group-writable so users in the group
103can write to tape devices.
104.Pp
105The
106.Xr shutdown 8
107program is executable only by root and members of the
108.Em operator
109group.
110.It Em mail
111Used by mail agents (like
112.Xr dma 8 ) .
113.Pp
114By default, root mail
115.Pq Pa /var/mail/root
116is in the
117.Em mail
118group.
119.It Em bin
120Historic group.
121Unused in modern
122.Fx .
123.It Em news
124Historic group.
125Unused in modern
126.Fx .
127.It Em man
128Historic group; used to be used for managing manual pages (see
129.Xr man 1 ) .
130.It Em games
131Used by various set-group-id games to maintain high-scores files
132and other common files in
133.Pa /var/games .
134The members of this group are also allowed to access
135.Pa /dev/input/event*
136device nodes (see
137.Xr hgame 4 ) .
138See also
139.Xr intro 6 .
140.It Em ftp
141Used to be used by
142.Xr sysinstall 8
143(which is now replaced with
144.Xr bsdinstall 8 )
145for setting up anonymous FTP.
146Unused in modern
147.Fx .
148.It Em staff
149Staff users, in contrast to guest users (see
150.Em guest
151group).
152Not used by
153.Fx ;
154available for the administrator's interpretation.
155See
156.Xr security 7
157for some recommendations on managing accounts in
158.Em staff
159group.
160.It Em sshd
161Primary group for the
162.Em sshd
163pseudo-user used by the
164.Xr sshd 8
165secure shell daemon.
166.It Em smmsp
167Primary group for user
168.Em smmsp ,
169which is used by
170.Xr sendmail 8
171if no non-root users were configured for running it.
172.Pp
173The name of the group means "SendMail Message Submission Program".
174.It Em mailnull
175Used by electronic mail transport agent
176.Xr sendmail 8
177as group for its default user
178.Em mailnull .
179.It Em guest
180Guest users, in contrast to staff users (see
181.Em staff
182group).
183Not used by
184.Fx ;
185available for the administrator's interpretation.
186.It Em video
187Used for access to
188.Pa /dev/drm/*
189devices,  which are used for GPU hardware acceleration.
190See
191.Xr drm 7 .
192.It Em realtime
193Used by
194.Xr mac_priority 4
195to allow members of this group to run threads and processes with
196realtime scheduling priority.
197See also
198.Xr rtprio 1 .
199.It Em idletime
200Used by
201.Xr mac_priority 4
202to allow members of this group to run processes with idle scheduling
203priority.
204See also
205.Xr idprio 1 .
206.It Em bind
207Used to be used as primary group for the
208.Em bind
209pseudo-user used by
210.Xr named 8
211Internet domain name server, which has been removed from the base system in
212.Fx 10.0 .
213.It Em unbound
214Primary group for the
215.Em unbound
216pseudo-user used by the
217.Xr local-unbound 8
218recursive DNS resolver.
219.It Em proxy
220Primary group for the
221.Em proxy
222pseudo-user used by the
223.Xr ftp-proxy 8
224proxy daemon with packet filters such as
225.Xr pf 4 .
226.It Em authpf
227Used by the set-group-id program
228.Xr authpf 8
229to configure authenticated gateways.
230.It Em _pflogd
231Primary group for the
232.Em _pflogd
233pseudo-user used by the
234.Xr pflogd 8
235log daemon with the
236.Xr pf 4
237packet filter.
238.It Em _dhcp
239Primary group for the
240.Em _dhcp
241pseudo-user used by the
242.Xr dhclient 8
243DHCP Client.
244.It Em dialer
245Users authorized to make outgoing modem calls (see
246.Xr cu 1
247and
248.Pa /dev/cuauN
249devices).
250.It Em network
251Historic group.
252Unused in modern
253.Fx .
254.It Em audit
255Primary group for the
256.Em auditdistd
257pseudo-user used by
258.Xr auditd 8
259and
260.Xr auditdistd 8
261audit daemons.
262.It Em www
263Historic group for accessing World Wide Web.
264Unused in modern
265.Fx .
266.It Em u2f
267Used for users who need to access
268.Pa /dev/u2f/*
269devices (see
270.Xr u2f 4 ) .
271.It Em ntpd
272Primary group for the
273.Em ntpd
274pseudo-user used by the
275.Xr ntpd 8
276network time protocol daemon.
277.It Em _ypldap
278Primary group for the
279.Em _ypldap
280pseudo-user used by
281.Xr ypldap 8
282daemon.
283.It Em hast
284Primary group for the
285.Em hast
286pseudo-user used by
287Highly Available Storage daemon
288.Xr hastd 8 .
289.It Em tests
290Primary group for the
291.Em tests
292pseudo-user used by
293automatic tests that request to run unprivileged.
294See
295.Xr tests 7 .
296.It Em nogroup
297Pseudo-group (fake group).
298It differs from group
299.Em nobody
300in way that
301.Em nogroup
302doesn't have a dedicated user for it.
303For instance, this group is used for users
304.Em tty
305and
306.Em kmem .
307.It Em nobody
308Primary group for the traditional
309.Em nobody
310pseudo-user.
311Modern practice is to assign to each different daemon its own separate
312pseudo-user account and group so that if one daemon is compromised it
313does not compromise all the other daemons.
314.Pp
315See also group
316.Em nogroup .
317.El
318.Sh FILES
319.Bl -tag -width "/usr/src/etc/group" -compact
320.It Pa /etc/group
321Main group permissions file.
322.It Pa /usr/src/etc/group
323Group permissions file for the base system.
324.It Pa /usr/ports/GIDs
325A list of GIDs (group IDs) reserved for ports (see
326.Xr ports 7 ) .
327.El
328.Pp
329See
330.Xr group 5
331for the format of abovementioned files.
332.Sh SEE ALSO
333.Xr chgrp 1 ,
334.Xr groups 1 ,
335.Xr id 1 ,
336.Xr newgrp 1 ,
337.Xr group 5 ,
338.Xr pw 8
339.Sh HISTORY
340The
341.Nm
342manual page appeared in
343.Nx 10.0
344and
345.Fx 15.1 .
346