Q. I will use the same .war file for my Production System. Will it have it???s own unique instance?
A. A Jenkins instance ID is generated first time the Jenkins war is started, and it is stored in your JENKINS_HOME. So you can use the same war on another host and will get a distinct ID, that will require a different dedicated license key.
Q. How do I get a license key?
A. This article shows this in detail.
Q. How do I upgrade from trial to production license?
A. Shown in detail here.
Q. Can I install CloudBees Jenkins Enterprise on top of my existing Jenkins community installation?
A. Yes. If the core version of CloudBees Jenkins Enterprise (e.g. 1.480.3) is at least as new the core version of your existing installation (e.g. 1.480.3, 1.466.2) then you can just replace your jenkins.war with the CloudBees Jenkins Enterprise download and start it up.
Q. Can I convert existing CloudBees Jenkins Enterprise installation to an OSS community Jenkins installation while keeping all the plugins?
A. Yes. Download jenkins.war from https://jenkins.io/ (make sure to pick up the version newer than your current CloudBees Jenkins Enterprise version), and overwrite jenkins.war with it. Next time you???ll start Jenkins, it???ll come up with Jenkins + all the plugins you had before.
Q. What do I need to do for uninstallation?
A. From a license perspective - nothing. You will need to delete the CloudBees plugins from your JENKINS_HOME (answered here)
Q. I am using a trial version of Jenkins Enterprise?
A. If you wish to not use CloudBees Jenkins Enterprise (look under the uninstallation section for steps to go back to Jenkins). If you wish to buy a license email (email@example.com or firstname.lastname@example.org)
Q. I have reached my limit on my paid version?
A. Contact sales (email@example.com) and once you have signed up a new contract, a standard support ticket with your instance id and number of executors would get you a license extension.