Application as Service on Centos 7

Question

Pretty new to Centos 7 and most of my earlier experiences were with Ubuntu. I have just set up an application on Centos 7 and I saw on their product website that to run the application as a Linux Service (Start at System Startup), this is the script that one needs to use.

#! /bin/sh
export JAVA_HOME="/usr/lib/jvm/jdk1.7.0_07"

startcmd='<PRODUCT_HOME>/bin/listener_mm.sh start > /dev/null &'
restartcmd='<PRODUCT_HOME>/bin/listener_mm.sh restart > /dev/null &'
stopcmd='<PRODUCT_HOME>/bin/listener_mm.sh stop > /dev/null &'

case "$1" in
start)
   echo "Starting the Listener Server ..."
   su -c "${startcmd}" user1
;;
restart)
   echo "Re-starting the Listener Server ..."
   su -c "${restartcmd}" user1
;;
stop)
   echo "Stopping the Listener Server ..."
   su -c "${stopcmd}" user1
;;
*)
   echo "Usage: $0 {start|stop|restart}"
exit 1
esac

Haha hope esac is not specific to other distro :?

So I created the script, substituted the correct values as per my enviroment, and added a Symbolic link to my script. I have couple of questions 1) The above script is perhaps for Ubuntu or another Linux Distro. So do I need to make any changes to the script? 2) How do I make this run as a service , for all users? I would want this to start at System Startup. Debian / Ubuntu has update-rc.d, and I guess i need to use chkconfig for this. Can I have any pointers on this? It happens to be a machine with few other things, so I am a little vary of experimenting and if anyone with experience on this could give me some pointers, it will be great.

I am doing some reading on systemd but any help will be really appreciated.

Thanks a ton.

Cheers, M.M

Answer 1

To run something on startup on CentOS 7, Fedora, and recent versions of Ubuntu, you need to create a systemd unit. What you have in your question is a legacy init script and is no longer necessary.

A simple unit file might look like this:

[Service]
Type=simple
ExecStart=/bin/myservice

[Install]
WantedBy=multi-user.target

Assuming that /bin/myservice runs in the foreground, the above is really all you need. You would place this into /etc/systemd/system/myservice.service if you are just setting things up on your own system, or /usr/lib/systemd/system/myservice.service if you are building a package for distribution, and then:

1. To start the service immediately: systemctl start myservice
2. To mark the service for automatic start next time you boot: systemctl enable myservice

Tools like chkconfig and update-rc.d are legacy tools that are not necessary in environments running systemd.