When Did I Last Reboot My Linux Box?

For any number of reasons, including bragging rights, you may want to know when you last rebooted your Linux computers. It’s actually pretty easy and I’ll show you how.

Crack open your terminal emulator, CTRL + ALT + T will often do it, and enter the following:

[code]last reboot[/code]

What will tell you when you last rebooted, who booted (system), the kernel used, date and time, and how long the system was up for.

For example:

[code]reboot system boot 5.4.0-52-generic Fri Nov 6 19:22 – 18:25 (9+23:02)
reboot system boot 5.4.0-52-generic Mon Nov 2 12:24 – 19:22 (4+06:57)
reboot system boot 5.4.0-51-generic Wed Oct 21 17:23 – 19:22 (16+02:58)[/code]

If you want to see the three most recent boots, you could just use the ‘head’ command.

[code]$ last reboot | head -3
reboot system boot 5.4.0-58-generic Thu Dec 31 14:56 still running
reboot system boot 5.4.0-58-generic Thu Dec 31 09:32 – 14:55 (05:22)
reboot system boot 5.4.0-58-generic Sat Dec 26 01:33 – 09:32 (5+07:59)[/code]

You can even use grep to see how many times you rebooted in a month, for example:

[code]$ last reboot | grep Nov
reboot system boot 5.4.0-54-generic Mon Nov 30 14:28 – 14:20 (3+23:51)
reboot system boot 5.4.0-54-generic Sat Nov 28 15:24 – 14:13 (1+22:48)
reboot system boot 5.4.0-54-generic Fri Nov 27 15:41 – 15:10 (23:29)
reboot system boot 5.4.0-54-generic Wed Nov 25 16:44 – 15:14 (1+22:29)
reboot system boot 5.4.0-53-generic Wed Nov 18 17:03 – 16:19 (6+23:15)
reboot system boot 5.4.0-53-generic Tue Nov 17 18:26 – 16:55 (22:29)
reboot system boot 5.4.0-53-generic Mon Nov 16 19:09 – 17:11 (22:01)
reboot system boot 5.4.0-53-generic Mon Nov 16 18:25 – 18:25 (00:00)
reboot system boot 5.4.0-52-generic Fri Nov 6 19:22 – 18:25 (9+23:02)
reboot system boot 5.4.0-52-generic Mon Nov 2 12:24 – 19:22 (4+06:57)[/code]

And there you have it. It’s much easier than you might think.