1TIMEDATECTL(1)                    timedatectl                   TIMEDATECTL(1)
2
3
4

NAME

6       timedatectl - Control the system time and date
7

SYNOPSIS

9       timedatectl [OPTIONS...] {COMMAND}
10

DESCRIPTION

12       timedatectl may be used to query and change the system clock and its
13       settings, and enable or disable time synchronization services.
14
15       Use systemd-firstboot(1) to initialize the system time zone for mounted
16       (but not booted) system images.
17
18       timedatectl may be used to show the current status of time
19       synchronization services, for example systemd-timesyncd.service(8).
20

COMMANDS

22       The following commands are understood:
23
24       status
25           Show current settings of the system clock and RTC, including
26           whether network time synchronization is active. If no command is
27           specified, this is the implied default.
28
29       show
30           Show the same information as status, but in machine readable form.
31           This command is intended to be used whenever computer-parsable
32           output is required. Use status if you are looking for formatted
33           human-readable output.
34
35           By default, empty properties are suppressed. Use --all to show
36           those too. To select specific properties to show, use --property=.
37
38       set-time [TIME]
39           Set the system clock to the specified time. This will also update
40           the RTC time accordingly. The time may be specified in the format
41           "2012-10-30 18:17:16".
42
43       set-timezone [TIMEZONE]
44           Set the system time zone to the specified value. Available
45           timezones can be listed with list-timezones. If the RTC is
46           configured to be in the local time, this will also update the RTC
47           time. This call will alter the /etc/localtime symlink. See
48           localtime(5) for more information.
49
50       list-timezones
51           List available time zones, one per line. Entries from the list can
52           be set as the system timezone with set-timezone.
53
54       set-local-rtc [BOOL]
55           Takes a boolean argument. If "0", the system is configured to
56           maintain the RTC in universal time. If "1", it will maintain the
57           RTC in local time instead. Note that maintaining the RTC in the
58           local timezone is not fully supported and will create various
59           problems with time zone changes and daylight saving adjustments. If
60           at all possible, keep the RTC in UTC mode. Note that invoking this
61           will also synchronize the RTC from the system clock, unless
62           --adjust-system-clock is passed (see above). This command will
63           change the 3rd line of /etc/adjtime, as documented in hwclock(8).
64
65       set-ntp [BOOL]
66           Takes a boolean argument. Controls whether network time
67           synchronization is active and enabled (if available). If the
68           argument is true, this enables and starts the first existing
69           network synchronization service. If the argument is false, then
70           this disables and stops the known network synchronization services.
71           The way that the list of services is built is described in systemd-
72           timedated.service(8).
73
74   systemd-timesyncd Commands
75       The following commands are specific to systemd-timesyncd.service(8).
76
77       timesync-status
78           Show current status of systemd-timesyncd.service(8). If --monitor
79           is specified, then this will monitor the status updates.
80
81       show-timesync
82           Show the same information as timesync-status, but in machine
83           readable form. This command is intended to be used whenever
84           computer-parsable output is required. Use timesync-status if you
85           are looking for formatted human-readable output.
86
87           By default, empty properties are suppressed. Use --all to show
88           those too. To select specific properties to show, use --property=.
89
90       ntp-servers INTERFACE SERVER...
91           Set the interface specific NTP servers. This command can be used
92           only when the interface is managed by systemd-networkd.
93
94       revert INTERFACE
95           Revert the interface specific NTP servers. This command can be used
96           only when the interface is managed by systemd-networkd.
97

OPTIONS

99       The following options are understood:
100
101       --no-ask-password
102           Do not query the user for authentication for privileged operations.
103
104       --adjust-system-clock
105           If set-local-rtc is invoked and this option is passed, the system
106           clock is synchronized from the RTC again, taking the new setting
107           into account. Otherwise, the RTC is synchronized from the system
108           clock.
109
110       --monitor
111           If timesync-status is invoked and this option is passed, then
112           timedatectl monitors the status of systemd-timesyncd.service(8) and
113           updates the outputs. Use Ctrl+C to terminate the monitoring.
114
115       -a, --all
116           When showing properties of systemd-timesyncd.service(8), show all
117           properties regardless of whether they are set or not.
118
119       -p, --property=
120           When showing properties of systemd-timesyncd.service(8), limit
121           display to certain properties as specified as argument. If not
122           specified, all set properties are shown. The argument should be a
123           property name, such as "ServerName". If specified more than once,
124           all properties with the specified names are shown.
125
126       --value
127           When printing properties with show-timesync, only print the value,
128           and skip the property name and "=".
129
130       -H, --host=
131           Execute the operation remotely. Specify a hostname, or a username
132           and hostname separated by "@", to connect to. The hostname may
133           optionally be suffixed by a port ssh is listening on, separated by
134           ":", and then a container name, separated by "/", which connects
135           directly to a specific container on the specified host. This will
136           use SSH to talk to the remote machine manager instance. Container
137           names may be enumerated with machinectl -H HOST. Put IPv6 addresses
138           in brackets.
139
140       -M, --machine=
141           Execute operation on a local container. Specify a container name to
142           connect to, optionally prefixed by a user name to connect as and a
143           separating "@" character. If the special string ".host" is used in
144           place of the container name, a connection to the local system is
145           made (which is useful to connect to a specific user's user bus:
146           "--user --machine=lennart@.host"). If the "@" syntax is not used,
147           the connection is made as root user. If the "@" syntax is used
148           either the left hand side or the right hand side may be omitted
149           (but not both) in which case the local user name and ".host" are
150           implied.
151
152       -h, --help
153           Print a short help text and exit.
154
155       --version
156           Print a short version string and exit.
157
158       --no-pager
159           Do not pipe output into a pager.
160

EXIT STATUS

162       On success, 0 is returned, a non-zero failure code otherwise.
163

ENVIRONMENT

165       $SYSTEMD_LOG_LEVEL
166           The maximum log level of emitted messages (messages with a higher
167           log level, i.e. less important ones, will be suppressed). Either
168           one of (in order of decreasing importance) emerg, alert, crit, err,
169           warning, notice, info, debug, or an integer in the range 0...7. See
170           syslog(3) for more information.
171
172       $SYSTEMD_LOG_COLOR
173           A boolean. If true, messages written to the tty will be colored
174           according to priority.
175
176           This setting is only useful when messages are written directly to
177           the terminal, because journalctl(1) and other tools that display
178           logs will color messages based on the log level on their own.
179
180       $SYSTEMD_LOG_TIME
181           A boolean. If true, console log messages will be prefixed with a
182           timestamp.
183
184           This setting is only useful when messages are written directly to
185           the terminal or a file, because journalctl(1) and other tools that
186           display logs will attach timestamps based on the entry metadata on
187           their own.
188
189       $SYSTEMD_LOG_LOCATION
190           A boolean. If true, messages will be prefixed with a filename and
191           line number in the source code where the message originates.
192
193           Note that the log location is often attached as metadata to journal
194           entries anyway. Including it directly in the message text can
195           nevertheless be convenient when debugging programs.
196
197       $SYSTEMD_LOG_TID
198           A boolean. If true, messages will be prefixed with the current
199           numerical thread ID (TID).
200
201           Note that the this information is attached as metadata to journal
202           entries anyway. Including it directly in the message text can
203           nevertheless be convenient when debugging programs.
204
205       $SYSTEMD_LOG_TARGET
206           The destination for log messages. One of console (log to the
207           attached tty), console-prefixed (log to the attached tty but with
208           prefixes encoding the log level and "facility", see syslog(3), kmsg
209           (log to the kernel circular log buffer), journal (log to the
210           journal), journal-or-kmsg (log to the journal if available, and to
211           kmsg otherwise), auto (determine the appropriate log target
212           automatically, the default), null (disable log output).
213
214       $SYSTEMD_PAGER
215           Pager to use when --no-pager is not given; overrides $PAGER. If
216           neither $SYSTEMD_PAGER nor $PAGER are set, a set of well-known
217           pager implementations are tried in turn, including less(1) and
218           more(1), until one is found. If no pager implementation is
219           discovered no pager is invoked. Setting this environment variable
220           to an empty string or the value "cat" is equivalent to passing
221           --no-pager.
222
223       $SYSTEMD_LESS
224           Override the options passed to less (by default "FRSXMK").
225
226           Users might want to change two options in particular:
227
228           K
229               This option instructs the pager to exit immediately when Ctrl+C
230               is pressed. To allow less to handle Ctrl+C itself to switch
231               back to the pager command prompt, unset this option.
232
233               If the value of $SYSTEMD_LESS does not include "K", and the
234               pager that is invoked is less, Ctrl+C will be ignored by the
235               executable, and needs to be handled by the pager.
236
237           X
238               This option instructs the pager to not send termcap
239               initialization and deinitialization strings to the terminal. It
240               is set by default to allow command output to remain visible in
241               the terminal even after the pager exits. Nevertheless, this
242               prevents some pager functionality from working, in particular
243               paged output cannot be scrolled with the mouse.
244
245           See less(1) for more discussion.
246
247       $SYSTEMD_LESSCHARSET
248           Override the charset passed to less (by default "utf-8", if the
249           invoking terminal is determined to be UTF-8 compatible).
250
251       $SYSTEMD_PAGERSECURE
252           Takes a boolean argument. When true, the "secure" mode of the pager
253           is enabled; if false, disabled. If $SYSTEMD_PAGERSECURE is not set
254           at all, secure mode is enabled if the effective UID is not the same
255           as the owner of the login session, see geteuid(2) and
256           sd_pid_get_owner_uid(3). In secure mode, LESSSECURE=1 will be set
257           when invoking the pager, and the pager shall disable commands that
258           open or create new files or start new subprocesses. When
259           $SYSTEMD_PAGERSECURE is not set at all, pagers which are not known
260           to implement secure mode will not be used. (Currently only less(1)
261           implements secure mode.)
262
263           Note: when commands are invoked with elevated privileges, for
264           example under sudo(8) or pkexec(1), care must be taken to ensure
265           that unintended interactive features are not enabled. "Secure" mode
266           for the pager may be enabled automatically as describe above.
267           Setting SYSTEMD_PAGERSECURE=0 or not removing it from the inherited
268           environment allows the user to invoke arbitrary commands. Note that
269           if the $SYSTEMD_PAGER or $PAGER variables are to be honoured,
270           $SYSTEMD_PAGERSECURE must be set too. It might be reasonable to
271           completely disable the pager using --no-pager instead.
272
273       $SYSTEMD_COLORS
274           Takes a boolean argument. When true, systemd and related utilities
275           will use colors in their output, otherwise the output will be
276           monochrome. Additionally, the variable can take one of the
277           following special values: "16", "256" to restrict the use of colors
278           to the base 16 or 256 ANSI colors, respectively. This can be
279           specified to override the automatic decision based on $TERM and
280           what the console is connected to.
281
282       $SYSTEMD_URLIFY
283           The value must be a boolean. Controls whether clickable links
284           should be generated in the output for terminal emulators supporting
285           this. This can be specified to override the decision that systemd
286           makes based on $TERM and other conditions.
287

EXAMPLES

289       Show current settings:
290
291           $ timedatectl
292                          Local time: Thu 2017-09-21 16:08:56 CEST
293                      Universal time: Thu 2017-09-21 14:08:56 UTC
294                            RTC time: Thu 2017-09-21 14:08:56
295                           Time zone: Europe/Warsaw (CEST, +0200)
296           System clock synchronized: yes
297                         NTP service: active
298                     RTC in local TZ: no
299
300       Enable network time synchronization:
301
302           $ timedatectl set-ntp true
303           ==== AUTHENTICATING FOR org.freedesktop.timedate1.set-ntp ===
304           Authentication is required to control whether network time synchronization shall be enabled.
305           Authenticating as: user
306           Password: ********
307           ==== AUTHENTICATION COMPLETE ===
308
309
310
311           $ systemctl status systemd-timesyncd.service
312           ● systemd-timesyncd.service - Network Time Synchronization
313              Loaded: loaded (/usr/lib/systemd/system/systemd-timesyncd.service; enabled)
314              Active: active (running) since Mo 2015-03-30 14:20:38 CEST; 5s ago
315                Docs: man:systemd-timesyncd.service(8)
316            Main PID: 595 (systemd-timesyn)
317              Status: "Using Time Server 216.239.38.15:123 (time4.google.com)."
318              CGroup: /system.slice/systemd-timesyncd.service
319                      └─595 /usr/lib/systemd/systemd-timesyncd
320           ...
321
322       Show current status of systemd-timesyncd.service(8):
323
324           $ timedatectl timesync-status
325                  Server: 216.239.38.15 (time4.google.com)
326           Poll interval: 1min 4s (min: 32s; max 34min 8s)
327                    Leap: normal
328                 Version: 4
329                 Stratum: 1
330               Reference: GPS
331               Precision: 1us (-20)
332           Root distance: 335us (max: 5s)
333                  Offset: +316us
334                   Delay: 349us
335                  Jitter: 0
336            Packet count: 1
337               Frequency: -8.802ppm
338
339

SEE ALSO

341       systemd(1), hwclock(8), date(1), localtime(5), systemctl(1), systemd-
342       timedated.service(8), systemd-timesyncd.service(8), systemd-
343       firstboot(1)
344
345
346
347systemd 250                                                     TIMEDATECTL(1)
Impressum