Yup, I agree — but that simply rewrites the question to be:
"Curious if anyone has particular hardware they like for OOB / serial management, similar to OpenGear, but preferably with 5G support, which can be a spoke that dials in to the central OOB hub, and the OOB hub doesn't care what IP they come from, using certificates or PSK for identity, instead of IP."
I've been on the same quest, and I have some additional requests / features. Ideally it:
1: would be small - my particular use-case is for a "traveling rack", and so 0U is preferred.
2: would be fairly cheap.
3: would not be a Raspberry-Pi, a USB hub and USB-to-serial cables. We tried that for a while, and it was clunky — the SD card died a few times (and jumped out entirely once!), people kept futzing with the OS and fighting over which console software to use, installing other packages, etc.
4: support modern SSH clients (it seems like you shouldn't have to say this, but… )
5: actually be designed as a termserver - the current thing we are using doesn't really understand terminals, and so we need to use 'socat -,raw,echo=0,escape=0x1d TCP:<termserver>:<port>' to get things like tab-completion and "up-arrow for last command" to work.
6: support logging of serial (e.g crash-messages) to some sort of log / buffer / similar (it's useful to be able to see what a device barfed all over the console when it crashes.
The Get Console Airconsole TS series meets many of these requirements, but it doesn't do #6. It also doesn't really feel like they have been updating / maintaining these.
Yes, I fully acknowledge that #3 falls into the "Doctor, Doctor, it hurts when I do this" camp, but, well…
W