The first version of Plex was a port of parts of the Xbox program XBMC to MacOS X (which has a lot more in common with Linux than Windows) - you can still see this history in the paths where Plex installs to on Linux. I’m not sure where you heard that it was originally designed to run on Windows.
Running everything via docker solves both problems no matter which OS you choose since the underlying OS doesn't matter.
Also recommend this because you can have a single docker compose file that will boot all your servers automatically instead of having to boot them individually on restarts.
Since you mentioned Plex, you can also incorporate your *arr stack/torrent clients (more complicated depending on which) into this if you're using it.
Running everything via docker solves both problems no matter which OS you choose since the underlying OS doesn't matter.
Yes, but also no.
Long story short: you can't run Windows containers on Linux. And to run Linux containers on Windows requires essentially running Linux on Windows, and then the Docker engine on Linux. (See also: running Linux containers on OS X.)
There do exist multi-arch container images, but that's the result of proper planning. One example: https://hub.docker.com/_/hello-world
More info: https://hackernoon.com/how-to-run-docker-linux-containers-natively-on-windows-ti1i3uxr
Did not know you can't run Windows containers on Linux interesting. Immediately assumed it was available but such a rare niche case.
And to run Linux containers on Windows requires essentially running Linux on Windows, and then the Docker engine on Linux.
I will say this is far easier than it sounds, it's essentially just enabling WSL2 aland configuring volumes properly. I was trying not to intimidate someone who's newer to a more complex hosting architectures
I installed Docker for Windows and spent weeks trying to get a NextCloud server running, with no luck, reading everything I could find. I finally signed up for a turnkey server in the EU for a reasonable price but the lag was unbearable, so I thanked them and canceled. I'm a complete newb with anything that is non-local. I've spent weeks finding workarounds for closed-source, out-of-business P:OS systems
I've got Plex running on 2 non-Windows systems: Raspberry Pi (Linux Docker container) and TrueNAS (FreeBSD jail). No issues.
If I could suggest something....
Try setting up a Linux VM on Windows. I'm not a Windows guy, so you might need to research how to do this. My go-to would be VirtualBox; I don't know if Hyper-V supports non-Windows VMs, and I'm not intimately familiar with setting up WSL.
Going the VM route will let you kick the Linux tires without committing to more hardware. Or, you could get a Raspberry Pi. External USB drive optional, since you should be able to configure Windows to share your library over the network and just have your Pi mount it.
Hyper-V is absolutely the way to go here. Linux is quite well supported.
I was in a similar situation and finally switched to Linux. The terrible state of parity storage spaces (reliability, speed) and some issues with HW transcoding made me do it.
Now I have one truenas server for storage (ZFS is so much better) and one proxmox server for everything else. Plex is running absolutely perfectly in a container, with HW acceleration.
If you go the proxmox route you might find the scripts here useful: https://tteck.github.io/Proxmox/
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