I followed the directions on https://www.theforeman.org/plugins/katello/3.13/installation/index.html including the fact that it says not to install on a current Foreman install or it’ll bork everything. So now it appears I’ve got two Foreman installs. The main one and then the Katello one. Is this what I was supposed to end up with? How do I now say that the main Foreman uses the Katello Foreman to provision hosts that have registered with the first Foreman I set up? I expected that, as a plugin, Katello was going to run on my Foreman instance.
I can’t see anything about this in the docs, but I may not know what to look for an so may be overlooking something obvious.
short answer: Yes, you ended up with two Foreman instances. In your situation, that is somewhat expected.
Despite Katello beeing labled as a plugin (because it technically is one), it bahaves differenty when compared to other plugins. As you have correctly read from the plugin manual, Katello can not be installed on top of an existing Foreman installation. You are in fact expected to setup your Foreman with Katello directly if you intend to use it’s features.
In your case, where you want to switch to using the Katello features, I fear the only feasable option would be to use the new Foreman server with Katello and migrate your existing configuration and systems over to that.