Jenkins stores all the data files inside this directory in the file system. You can change this by either:
  1. Using your web container's admin tool to set the JENKINS_HOME environment entry.
  2. Setting the environment variable JENKINS_HOME before launching your web container.
  3. (Not recommended) modifying web.xml in jenkins.war (or its expanded image in your web container).
This value cannot be changed while Jenkins is running. This entry is mostly for you to make sure that your configuration is taking effect.