How to create a service on Ubuntu Upstart

Question

I have a Java executable program that I can run by typing java -jar abc.jar in terminal. How can I run it as a service? I want to run it as a service like by typing service abc start.

Answer 1

Make sure you're on 14.04. Ubuntu 16.04 (and above) uses systemd, not Upstart.

A Upstart script is a script file placed at /etc/init/ and ending in .conf.

It requires 2 sections: one to indicate when to start, and another with the command to execute.

The easiest script to start with your sample is:

# myprogram.conf
start on filesystem
exec /usr/bin/java -jar /path_to/program

Created as root under /etc/init/myprogram.conf.

If your script requires more than one command line, use the script section instead of the exec line:

# myprogram.conf
start on filesystem
script
    /usr/bin/java -jar /path_to/program
    echo "Another command"
end script

To enable bash completion for your service, add a symlink into /etc/init.d folder:

sudo ln -s /etc/init/myprogram.conf /etc/init.d/myprogram

Then try start and stop it:

sudo service myprogram start

According the upstart cookbook, you can create pre-start/post-start and pre-stop/post-stop commands to be executed.

Additionally, I read you want to check if a process is running. Check this question and maybe use the pre-start section.

Answer 2

You need to create an upstart. http://upstart.ubuntu.com/getting-started.html

Upstart is (IMHO) a disaster compared to good ol' SysV init scripts. Upstart is FAR more effort with little upside to the added work. With that said, I suspect there will be a few upstart defenders out there that will take me to task for me stating the obvious ;-)