1

I would like to see the start/stop times of a Linux PC.

I found this command, but the output is wrong:

last reboot -F
reboot   system boot  4.15.0-46-generi Thu Mar 14 10:04:27 2019 - Thu Mar 14 15:31:11 2019  (05:26)

That's not true. Instead of 10:04 it is 09:04.

See related question: https://askubuntu.com/questions/854567/last-reboot-is-missing-one-hour/859782

How can I see the correct start/stop times on Ubuntu 18.04?

  • Any chance the reboot was during Daylight saving time and clock was adjusted one hour? – Dextro67 Mar 15 '19 at 9:31
  • @Dextro67 I did not change the clock by hand, and the wrong output of the reboot commands happens every day. I don't care for the internals, I just want reliable numbers. – guettli Mar 15 '19 at 9:40
  • Then set the system time zone to UTC. – Michael Hampton Mar 18 '19 at 17:08
  • @MichaelHampton I need to change the system time zone, just to be able to get the start/stop times reliably? OK, this was new to me. – guettli Mar 19 '19 at 7:51
  • @guettli Please, do not cross post. You've already asked the same question ~2 years ago. – Paradox Mar 20 '19 at 16:31
8
+50
# timestamps corresponds to your current timezone
user@node:~$ journalctl --list-boots
-3 0f2fcb9569384a2aa2d5492505f86cda Tue 2018-11-27 16:45:22 CET—Thu 2018-11-29 10:10:07 CET
-2 646787bd244d4230a5986f00207c1e8c Sun 2019-02-24 19:50:23 CET—Tue 2019-02-26 22:49:29 CET
-1 c922041a9a3847babd51ac79dd06923c Wed 2019-02-27 08:27:28 CET—Sun 2019-03-03 08:52:52 CET
 0 0aa03fbca4bf4976b922f9f77c63f65a Sun 2019-03-03 09:02:47 CET—Mon 2019-03-18 17:10:08 CET

# timestamps corresponds to universal timezone
user@node:~$ journalctl --list-boots --utc
-3 0f2fcb9569384a2aa2d5492505f86cda Tue 2018-11-27 15:45:22 UTC—Thu 2018-11-29 09:10:07 UTC
-2 646787bd244d4230a5986f00207c1e8c Sun 2019-02-24 18:50:23 UTC—Tue 2019-02-26 21:49:29 UTC
-1 c922041a9a3847babd51ac79dd06923c Wed 2019-02-27 07:27:28 UTC—Sun 2019-03-03 07:52:52 UTC
 0 0aa03fbca4bf4976b922f9f77c63f65a Sun 2019-03-03 08:02:47 UTC—Mon 2019-03-18 16:10:08 UTC

UTC timezone is universal that's why it is useful to avoid any daylight saving time misunderstanding issues.

From journalctl man page :

       --list-boots
           Show a tabular list of boot numbers (relative to the current boot), their IDs, and the timestamps of the first and last message pertaining to the boot.

PS : in case you have only one line returned by journalctl, just create folder /var/log/journal to enable multiple on-disk journal retention

  • Nice! Works, I get the correct time: "Mon 2019-03-18 08:38:11 CET—Mon 2019-03-18 17:01:44 CET" and last reboot is still wrong by one hour: " 09:38 - 17:01" – guettli Mar 19 '19 at 7:57
0

Grepping rsyslog stsrt/stops from /var/log/messages would likely suit your needs as that’s one of the first things to start and last things to stop on shutdown.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.