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I need my script to be executed a minute after each reboot. When I apply @reboot in my crontab it is too early for my script - I want the script to be executed after all other tasks that are routinely run on reboot. How might I run the script sometime after reboot?

John Smith
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Yurij73
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    Why is it too early? Maybe an init script would be more suitable (by regarding dependencies, e.g. this script needs networking to be set up first)? – sr_ Dec 07 '12 at 10:11
  • my script need be executed after all others, the last in short words – Yurij73 Dec 07 '12 at 10:22
  • since your job needs to be executed after everything and since the concept of everything is quite variable (addition of a new autostart@reboot application is not so uncommon), I think it is up to you to place your job into the rc scripts in a way that servers your purpose. Putting your task at the bottom of tasks specified in /etc/rc.local is usually what you want, but depending on your system's startup configuration, this might not hold true all the time. So, test it and see if it works for you. – MelBurslan Dec 07 '12 at 15:49
  • Sounds like a case for Upstart? – nafg Nov 27 '13 at 10:29
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    Just had a similar situation where I had to use two @reboot lines because the first command "took over", although maybe a single & could resolve this. Anyway, this worked for me, e.g.: @reboot mongod --port 27017 /var/lib/mongodb and @reboot sleep 60 && /use/bin/node /home/me/server.js. Had to use the sleep to give mongo a chance to boot up. Maybe there's a better way but this works for now. –  Feb 08 '21 at 13:04

3 Answers3

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Is the script only ever intended to run one minute after boot up, or can it be used at other times, too? In the former case, you can add sleep 60 to the beginning of your script, or in the latter case, add it to the crontab file:

@reboot sleep 60 && my_script.sh

As has been pointed out by sr_, though, perhaps you are tackling this in the wrong way, and a proper init.d or rc.d script would be a more robust solution.

D_Bye
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If you need to execute something after reboot when network will become available, for example, you can write systemd unit that will be executed at required time (of course this will work only on systems with systemd).

To do so create file /etc/systemd/system/my_script.service with following contents:

[Unit]
Description=My script that requires network
After=network.target

[Service]
Type=oneshot
ExecStart=/full/path/to/my_script.sh

[Install]
WantedBy=multi-user.target

Then execute:

sudo systemctl daemon-reload
sudo systemctl enable my_script

You're done!

Envek
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I would use at. As in:

@reboot echo /root/bin/do_the_stuff | at now + 2 minutes
# at assigns it an execution time truncated to whole minutes,
# so this means it will execute in 1--2 minutes.

... with the added mentioned caveat that if what you really want is to run it after all other things, you should check how to do that in the init that your OS is using.

clacke
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