java daemon
How to run a Java Program as a daemon on Debian & Ubuntu
Borrowed from:
How to run a Java Program as a daemon (service) on Linux (SUSE/openSUSE) using a shell script http://www.source-code.biz/snippets/java/7.htm
I just adapted it to Debian 7
Changes I made (so far):
- no external dependancy to other scripts : removed dependancy to rc.status (not existing in Debian)
- 1 or 2 quickfix (chown was absent, shell variables, checkProcessIsOurService..)
- replaced sudo by su (why sudo?)
- I separated the derived variables from the main variables
- you can uncheck to debug variable to check variables values
Why I did it?
I first used the Apache Jakarta Commons Daemon package (Jsvc) http://jakarta.apache.org/commons/daemon/. The problem is... on prod, after a while it ate 80% CPU. For no reason (because it happens when the program is waiting on inotify events). No time to try to fix this.
(side note: I did not consider the Java Service Wrapper http://wrapper.tanukisoftware.org/: not open source, it will not run on my servers)
Then I was about to write a quick script based on nohup, when I found that one. Perfect. It use 100% shell, and detaches correclty the java process: Great.
I know there exists a standard scripts with Debian, but honestly, I find this one easier to debug/understand than the /etc/init.d/skeleton. start-stop-deamon is far too opaque to me.
Features
The shell script (javaDaemonTest.sh) provides the following functionality:
- Start/stop the Java daemon process, according to the Linux system init script convention.
- Run the Java daemon as a different (non-root) Linux user.
- Log error messages and redirect StdOut/StdErr output into a log file.
- Install/uninstall the daemon as a Linux service. (The "install" procedure installs the script in /etc/init.d, enables the service in the configured default runlevels, creates the "rc" command (symlink) and creates the Linux user (as a system account) and group if necessary).
Thanks
Thanks to the original Author Christian d'Heureuse for sharing this.