While tooting on some of my user fellow comments I found out this question quite intrinsic in nature.
Question:
I want to create a cron job which executes daiy at assigned time and it restart the ubuntu server.
I try to add reboot only in cron, but it is not working, whereas it works when I try to execute it from CLI.
Please advise, what command should I add in cron, so that it reboot the server daily at specific time.
Best possible solution:
You need to run the following command:
/sbin/shutdown -r now
with root pirviliges. The way to do it is to use root’s crontab, not your user crontab. A sudo before the usual crontab command does that:
sudo crontab -e
Tip: You can switch the shell’s standard editor for things like crontab and visudo with sudo update-alternatives --config editor and then select the editor of your choice.
Editing the crontab you should add the following line to your file:
# For more information see the manual pages of crontab(5) and cron(8)
#
# m h dom mon dow command
@daily root /sbin/shutdown -r now
Here is a shortcut for every day at midnight (equivalent to “0 0 * * *”).