1TIMEDATECTL(1) timedatectl TIMEDATECTL(1)
2
6 timedatectl - Control the system time and date
7
9 timedatectl [OPTIONS...] {COMMAND}
10
12 timedatectl may be used to query and change the system clock and its
13 settings, and enable or disable time synchronization services.
14 Use systemd-firstboot(1) to initialize the system time zone for mounted
16 (but not booted) system images.
17 timedatectl may be used to show the current status of time
19 synchronization services, for example systemd-timesyncd.service(8).
20
22 The following commands are understood:
23 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 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 By default, empty properties are suppressed. Use --all to show
36 those too. To select specific properties to show, use --property=.
37 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 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 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 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 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 systemd-timesyncd Commands
75 The following commands are specific to systemd-timesyncd.service(8).
76 timesync-status
78 Show current status of systemd-timesyncd.service(8). If --monitor
79 is specified, then this will monitor the status updates.
80 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 By default, empty properties are suppressed. Use --all to show
88 those too. To select specific properties to show, use --property=.
89 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 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
99 The following options are understood:
100 --no-ask-password
102 Do not query the user for authentication for privileged operations.
103 --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 --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 -a, --all
116 When showing properties of systemd-timesyncd.service(8), show all
117 properties regardless of whether they are set or not.
118 -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 --value
127 When printing properties with show-timesync, only print the value,
128 and skip the property name and "=".
129 -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 -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 -h, --help
153 Print a short help text and exit.
154 --version
156 Print a short version string and exit.
157 --no-pager
159 Do not pipe output into a pager.
160
162 On success, 0 is returned, a non-zero failure code otherwise.
163
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 $SYSTEMD_LOG_COLOR
173 A boolean. If true, messages written to the tty will be colored
174 according to priority.
175 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 $SYSTEMD_LOG_TIME
181 A boolean. If true, console log messages will be prefixed with a
182 timestamp.
183 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 $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 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 $SYSTEMD_LOG_TID
198 A boolean. If true, messages will be prefixed with the current
199 numerical thread ID (TID).
200 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 $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 $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 Note: if $SYSTEMD_PAGERSECURE is not set, $SYSTEMD_PAGER (as well
224 as $PAGER) will be silently ignored.
225 $SYSTEMD_LESS
227 Override the options passed to less (by default "FRSXMK").
228 Users might want to change two options in particular:
230 K
232 This option instructs the pager to exit immediately when Ctrl+C
233 is pressed. To allow less to handle Ctrl+C itself to switch
234 back to the pager command prompt, unset this option.
235 If the value of $SYSTEMD_LESS does not include "K", and the
237 pager that is invoked is less, Ctrl+C will be ignored by the
238 executable, and needs to be handled by the pager.
239 X
241 This option instructs the pager to not send termcap
242 initialization and deinitialization strings to the terminal. It
243 is set by default to allow command output to remain visible in
244 the terminal even after the pager exits. Nevertheless, this
245 prevents some pager functionality from working, in particular
246 paged output cannot be scrolled with the mouse.
247 See less(1) for more discussion.
249 $SYSTEMD_LESSCHARSET
251 Override the charset passed to less (by default "utf-8", if the
252 invoking terminal is determined to be UTF-8 compatible).
253 $SYSTEMD_PAGERSECURE
255 Takes a boolean argument. When true, the "secure" mode of the pager
256 is enabled; if false, disabled. If $SYSTEMD_PAGERSECURE is not set
257 at all, secure mode is enabled if the effective UID is not the same
258 as the owner of the login session, see geteuid(2) and
259 sd_pid_get_owner_uid(3). In secure mode, LESSSECURE=1 will be set
260 when invoking the pager, and the pager shall disable commands that
261 open or create new files or start new subprocesses. When
262 $SYSTEMD_PAGERSECURE is not set at all, pagers which are not known
263 to implement secure mode will not be used. (Currently only less(1)
264 implements secure mode.)
265 Note: when commands are invoked with elevated privileges, for
267 example under sudo(8) or pkexec(1), care must be taken to ensure
268 that unintended interactive features are not enabled. "Secure" mode
269 for the pager may be enabled automatically as describe above.
270 Setting SYSTEMD_PAGERSECURE=0 or not removing it from the inherited
271 environment allows the user to invoke arbitrary commands. Note that
272 if the $SYSTEMD_PAGER or $PAGER variables are to be honoured,
273 $SYSTEMD_PAGERSECURE must be set too. It might be reasonable to
274 completely disable the pager using --no-pager instead.
275 $SYSTEMD_COLORS
277 Takes a boolean argument. When true, systemd and related utilities
278 will use colors in their output, otherwise the output will be
279 monochrome. Additionally, the variable can take one of the
280 following special values: "16", "256" to restrict the use of colors
281 to the base 16 or 256 ANSI colors, respectively. This can be
282 specified to override the automatic decision based on $TERM and
283 what the console is connected to.
284 $SYSTEMD_URLIFY
286 The value must be a boolean. Controls whether clickable links
287 should be generated in the output for terminal emulators supporting
288 this. This can be specified to override the decision that systemd
289 makes based on $TERM and other conditions.
290
292 Show current settings:
293 $ timedatectl
295 Local time: Thu 2017-09-21 16:08:56 CEST
296 Universal time: Thu 2017-09-21 14:08:56 UTC
297 RTC time: Thu 2017-09-21 14:08:56
298 Time zone: Europe/Warsaw (CEST, +0200)
299 System clock synchronized: yes
300 NTP service: active
301 RTC in local TZ: no
302 Enable network time synchronization:
304 $ timedatectl set-ntp true
306 ==== AUTHENTICATING FOR org.freedesktop.timedate1.set-ntp ===
307 Authentication is required to control whether network time synchronization shall be enabled.
308 Authenticating as: user
309 Password: ********
310 ==== AUTHENTICATION COMPLETE ===
311 $ systemctl status systemd-timesyncd.service
315 ● systemd-timesyncd.service - Network Time Synchronization
316 Loaded: loaded (/usr/lib/systemd/system/systemd-timesyncd.service; enabled)
317 Active: active (running) since Mo 2015-03-30 14:20:38 CEST; 5s ago
318 Docs: man:systemd-timesyncd.service(8)
319 Main PID: 595 (systemd-timesyn)
320 Status: "Using Time Server 216.239.38.15:123 (time4.google.com)."
321 CGroup: /system.slice/systemd-timesyncd.service
322 └─595 /usr/lib/systemd/systemd-timesyncd
323 ...
324 Show current status of systemd-timesyncd.service(8):
326 $ timedatectl timesync-status
328 Server: 216.239.38.15 (time4.google.com)
329 Poll interval: 1min 4s (min: 32s; max 34min 8s)
330 Leap: normal
331 Version: 4
332 Stratum: 1
333 Reference: GPS
334 Precision: 1us (-20)
335 Root distance: 335us (max: 5s)
336 Offset: +316us
337 Delay: 349us
338 Jitter: 0
339 Packet count: 1
340 Frequency: -8.802ppm
341
344 systemd(1), hwclock(8), date(1), localtime(5), systemctl(1), systemd-
345 timedated.service(8), systemd-timesyncd.service(8), systemd-
346 firstboot(1)
347systemd 253 TIMEDATECTL(1)