I have been struggling to get serial comms going with a TESmart KVM because the ethernet interface is stupid and I lost comms after a misconfiguration and there

I have been struggling to get serial comms going with a TESmart KVM because the ethernet interface is stupid and I lost comms after a misconfiguration and there is no way to factory reset the device. That was not going any better and I ended up purchasing a null modem adapter (at an eye-wateringly high price) because of course I threw away a drawer full of serial adapters a decade ago.