I'm not entirely sure what happened. I was fooling around with an Aeotec Micro Switch G2 that has always been problematic dropping off my network and needing to be power cycled. A power cycle didn't work, so I tried to exclude and include it (neither of which worked, either). And then, shockingly, all my Z-Wave devices disappeared from the Z-Wave settings page at <my.ip>/hub/zwaveInfo. (For the record, I definitely DID NOT reset the radio by clicking the red button)
You don’t say what version Hubitat firmware. That might be important. I believe there was a recent fix to this, so you might want to update after you get them back.
I suggest that you reboot (not reset) the Z-wave radio. To do so:
Shut down the hub cleanly. Settings, Shutdown. When you get a red light on the front, remove power from the hub at the wall plug, not the micro USB, which is fragile and can break the solder joints to the PC board. Leave power off at least 30 seconds. Restore power, allow the hub to boot.
Rebooting the hub, alone, does not reboot the Z-wave radio.
A few of us have been there in this moment of panic. I know I have.
I wish the cause could be found and prevented. Lacking that, it would be great, if the Z-Wave radio’s API to the hub so provides, to have a way to reboot the Z-Wave radio without the shutdown, power off, power on, dance.
I tried that, actually. I disabled and enabled the radio to no effect.
It seems a silly thing to lose sleep over in retrospect, but I did have a fairly restless night. The pain of moving all my devices and automations from SmartThings to HE is not something I want to relive, and it’s the main thing holding me back from upgrading to a C-7.