The build strategy “Skip Initial Build On First Branch Indexing”
It is completely useless in our case.
It prevents any branch to build when it is first indexed. So far so good, but with a caveat.
It prevents Jenkins to build ALL branches on ALL projects, when adding a group.
Unfortunately, if adding new branches later, they will never build when first added, only on subsequent commit push to it. What if a branch never gets any more commits, then it will never build in Jenkins (unless someone manually runs it).
All we need is to prevent building when a project has been first created. Then all other branch indexing should build the branch.
I was testing out going from 600 Multibranch Pipeline jobs, and over to GitLab Group.
Adding one GitLab Group (we have more groups), that had 120 projects, it caused Jenkins to build all the branches on all those projects.
I did not count, but that is probably over a thousand builds.
Jenkins seriously needs a kill all builds button.
I have a script that I could run for stopping builds, but it did not work for GitLab Groups project builds.
First I had to take the build agent completely offline, so nothing started building.
Then I had to manually click cancel of hundreds of jobs. Insane!
I do not look forward to putting this GitLab Group in production.
I think I would have to disconnect the build agent. Then manually cancel all the jobs started.