How can I schedule a nightly reboot?

I'd use cron (should already be installed):

Edit crontab:

sudo crontab -e

The first time you might have to choose your preferred editor (like nano)

Insert a line like

0 4   *   *   *    /sbin/shutdown -r +5

at the bottom. Explanation:

m      h    dom        mon   dow       command
minute hour dayOfMonth Month dayOfWeek commandToRun

so the line

  0 4   *   *   *    /sbin/shutdown -r +5

would reboot your system every day at 4:05am. (4:00am + 5 minutes)

Ctrl+X, Y, Enter should get you out of crontab (if using nano)

Note: you might have to run crontab -e as root, because shutdown needs root. crontab -e opens a file in /tmp instead of the actual crontab so that it can check your new crontab for errors. If there are no errors, then your actual crontab will be updated.

Adding this to /etc/cron.daily/zz-reboot should work:

#!/bin/sh
shutdown -r now

And sudo chmod a+x /etc/cron.daily/zz-reboot. The "zz" prefix will force it to run last out of all the other scripts in that directory. Check /etc/crontab to see what time of day that will actually happen:

grep daily /etc/crontab | awk '{print $2 ":" $1}'

If that won't work, then a "regular" cron entry can work too, via sudo crontab -e

MINUTE HOUR * * * shutdown -r now

And finally, if you want to just do one-off reboots, you can use at:

echo "shutdown -r now" | sudo at 04:30

I have been working with cronjobs for about a month at my work and scheduling poweroff, and reboot. It's very simple. I know this was asked about 5 years ago, but if anyone still has problems, you can use this method and you will be set.

open the terminal (ctrl+T)

sudo nano /etc/crontab

scroll all the way to the bottom and enter the below command

00 6 * * * root reboot 

this is set for reboot at 6am everyday, and press enter

If you want to schedule poweroff at 11pm everyday you can enter

00 23 * * * root poweroff

I still need to figure out how to poweron a machine using cronjob when it's down. I will edit this answer once i figure it out.

P.S. this is my first ever answer posting on any forms; hope it helps someone!! :D