Question

On an Amazon S3 Linux instance, I have two scripts called start_my_app and stop_my_app which start and stop forever (which in turn runs my Node.js application). I use these scripts to manually start and stop my Node.js application. So far so good.

My problem: I also want to set it up such that start_my_app is run whenever the system boots up. I know that I need to add a file inside init.d and I know how to symlink it to the proper directory within rc.d, but I can’t figure out what actually needs to go inside the file that I place in init.d. I’m thinking it should be just one line, like, start_my_app, but that hasn’t been working for me.

Answer 1

The file you put in /etc/init.d/ have to be set to executable with:

chmod +x /etc/init.d/start_my_app

As pointed out by @meetamit, if it still does not run you might have to create a symbolic link to the file in /etc/rc.d/

ln -s /etc/init.d/start_my_app /etc/rc.d/

Please note that on the latest versions of Debian, this will not work as your script will have to be LSB compliant (provide at least the following actions: start, stop, restart, force-reload, and status):
https://wiki.debian.org/LSBInitScripts

As a note, you should always use the absolute path to files in your scripts instead of the relative one, it may solve unexpected issues:

/var/myscripts/start_my_app

Finally, make sure that you included the shebang on top of the file:

#!/bin/sh