Jenkins build fails with "Default Jenkinsfile not found"

Note: please note that Liferay has renamed its Liferay Experience Could offerings to Liferay SaaS (formerly LXC) and Liferay PaaS (formerly LXC-SM).

Issue

• We updated our CI service's version after deploying this change to our Infra environment, the Jenkins build fails and we also lose the Jenkins configuration:

Started by user customer
Running as customer
java.lang.IllegalArgumentException: Default Jenkinsfile not found. Check configuration.
	at org.jenkinsci.plugins.pipeline.multibranch.defaults.DefaultsBinder.create(DefaultsBinder.java:87)
	at org.jenkinsci.plugins.workflow.job.WorkflowRun.run(WorkflowRun.java:310)
	at hudson.model.ResourceController.execute(ResourceController.java:107)
	at hudson.model.Executor.run(Executor.java:449)
Finished: FAILURE

Environment

• Liferay PaaS

Resolution

1. Delete the CI service
2. Rename the volume name, like
   

   "volumes": {
      "ciData2": "/var/jenkins_home"
   }

3. Redeploy the changes