I wanted to run a command on our linux after its done rebooting, I saw that it can be done using crontab. I wanted to run this command
sudo ifdown eth0 && sudo ifup -v eth0
on the crontab can i just do:
@reboot sudo ifdown eth0 && sudo ifup -v eth0
or do i need to store that in a script?
thank you
2 Answers
A few notes here before this would work:
- Don't use
sudoin a cron job. Instead editroot's crontab instead of your own, e.g.sudo crontab -eand then enter commands withoutsudo. - As @mikewhatever mentioned, this is an odd use for
cron, and would likely be better placed in/etc/rc.localbefore theexit 0line. - If you tell us exactly what you're looking for, we might be able to direct you to a log or config option (restarting your network services at startup feels a little hackish).
- On most systems
@rebootshould also run after a hard shutdown or crash, but there are different cron implementations so YMMV. I've seen comments in different places asserting both.
EDIT (2016/02/17): Removed incorrect blurb on absolute paths; kudos @muru
EDIT (2016/10/17): Added shutdown note
EDIT (2017/09/11): Revised shutdown note. Not really sure on that one.
You can use crontab for this, but if you use sudo, then you will need a NOPASSWD rule in sudoers to do so. (See How to run a cron job using the sudo command.)
It would be simpler to edit /etc/rc.local and add these commands before the exit 0 line.
