Unable to run nohup command from jenkins as a background process

Question

UPDATE: Based on below discussion I have edited my answer for more accurate description.

I am trying to run a nohup command from jenkins. The full command is

nohup java -jar /home/.../jar/server-process-0.35.jar prod >> /var/../server-process-prod.log 2>&1 &

This command does not work. I can see status as success in jenkins but no java process in linux. When I do 'ps -ef | grep java'

However when I remove the last '&' , that is I change it from run in forground instead of background

It starts working. I can see the java process started.

The original command works fine If I run it on linux console.

I need to run it from jenkins in the original form that is as a backgorund process. So that it is independant of jenkins.

Any clues why is this happening?

Answer 1

Long story short, Jenkins kills all processes spawned by a job once that job finishes. To override this behavior, you need to set an environment variable.

The variable appears to vary from job type to job type. It used to be BUILD_ID, but for Pipeline jobs it is JENKINS_NODE_COOKIE, and there are several others mentioned in this answer.

So if you're running your command in Pipeline, it would look like this:

sh 'JENKINS_NODE_COOKIE=dontKillMe nohup java -jar /home/.../jar/server-process-0.35.jar prod >> /var/../server-process-prod.log 2>&1 &'

See the wiki on ProcessTreeKiller and this comment in the Jenkins Jira for more information.

Answer 2

In your jenkins shell script try:

  export BUILD_ID=dontKillMe
  nohup java -jar your_java_app.jar &

It worked for me!