I feel like Guides is the best place for this, but obviously move if needed.
I created octoprint_deploy as a tool for making multiple OctoPrint instances very quickly. It has since morphed a bit into a tool that creates something akin to OctoPi on virtually any linux installation (sorry, no Arch yet) very easily. This includes installation of OctoPrint, mjpg-streamer or ustreamer, haproxy, automatic udev entries based on printer serial number (or physical USB port), and support of automatically setting up USB cameras. It can also be used with OctoPi directly for creating multiple instances.
The workflow is to install linux, prepare the system (this gets needed packages, installs OctoPrint, streamer, etc.), and then to create a template instance with the admin user. This template instance is then used to create one or more instances, as required.
Multiple OctoPrint instances is not official supported, but myself and many others have found this to be extremely robust. I have been running 10 printers on a single linux box for ~5 years.
You can find octoprint_deploy and complete instructions here: GitHub - paukstelis/octoprint_deploy: Bash script for rapid deployment of multiple octoprint instance on a single machine