I did exactly this a few months ago on my NextCloud instance. Much sad ensued that evening.

I didn’t know most of these had specific names, and will almost certainly forget them the moment I close this post, but it’s cool to know them for 30 seconds

Having worked on them occasionally was about to confirm that, but somebody gave it more JPEG already and I can’t quite make it out. They do certain look like BNC/some other coaxial connector though and I’ve definitely have to troubleshoot very similar nightmarish setups