I have Jenkins version 2.346.2 running in an environment which is completely isolated from the Internet.
I want to point the Update Center URI to a local copy of the update-center.json file (which I will change the paths in so that the plugin files can be downloaded from a local repository). I have therefore downloaded the update-center.json and update-center.json.html files from updates.jenkins.io and changed the Update Site URL to http://localhost:8080/job/Admin/job/CreateUpdateFile/ws/local-update-center.json
However, when I click on the ‘Check Now’ button, I receive a 403 error:
You will notice from the screenshots above that I am using HTTP, not HTTPS so surely no security is required?? Is it because I am trying to access a file within Jenkins itself; would I be better to try and host it elsewhere??