Pros: we can keep installing plugins, as old versions might disappear.

Cons: the exercises might not "keep working" on the new versions of the plugins.

I think for a completely automated setup, it'd be nice to have some katas to show this.

https://awesomeopensource.com/project/jenkinsci/hashicorp-vault-plugin?categoryPage=11

Flesh out the kata:
https://github.com/praqma-training/jcasc-katas/blob/master/configuring-plugins/README.md

I found this small snippet on StackOverflow. It outputs all the plugins that are installed, and not just the ones listed in the plugins.txt file.

  Jenkins.instance.pluginManager.plugins.each{
    plugin ->
    println ("${plugin.getShortName()}: ${plugin.getVersion()}");
  }

https://stackoverflow.com/questions/9815273/how-to-get-a-list-of-installed-jenkins-plugins-with-name-and-version-pair

https://github.com/praqma-training/jcasc-katas/blob/master/jobs/README.md

Might need to be chopped into several katas

https://github.com/praqma-training/jcasc-katas/blob/master/build-agents/README.md

For the basic exercise, perhaps also $JENKINS_HOME/jenkins.yml could be mentioned as an alternative to mounting a casc-config directory in $JENKINS_HOME.

In 1. basic system configuration, you are supposed to make JCasC fail uppon reload.
In older versions of Jenkins, the stacktrace was just below the the error, now you will get something like this:
A problem occurred while processing the request.

Logging ID=e07a2e33-21af-4148-ba43-4842c5932758

Task: change the description to add the following:
Guide people into Jenkins -> System Log to see the error.