Long time hubitat user -- c4, c5, c7 -- c7 is the only one with zwave radio on, but on 6/10 it lost all 41 zwave devices. I was on 188.8.131.52 when the problem occurred.
I'd not logged into the device since 5/30 to do an update to 184.108.40.206, so I have a backup from that day and previous version - 220.127.116.11. I hadn't updated in a while, as everything was stable.
6/10, I noticed several of rules automations involving my zwave wall switches were functioning incorrectly at sunset, so I logged into the Hubitat C7 -- the devices list in the Devices tab but I wasn't receiving any logs and I couldn't control the devices directly from the Device entry. Going into Settings --> ZWave Details, there were no devices. I attempted a ZWave Repair -- which hung for 15+ minutes before I gave up on completing and accessed the UI main page again and rebooted the device. The C7 came back with 18.104.22.168 and showed devices in Devices but none in Z-Wave Details.
I accessed the Diagnostic Tool page and rolled the software back to 22.214.171.124 (with reboot) and then did a restore of the backup file (with reboot) and still devices in Devices, but nothing in the Z-Wave Details.
Dead zwave radio?
You will need to power cycle the hub. Settings: Shutdown. When the LED goes red, unplug it, wait 15 seconds, power it back up.
The reason is: the Z-Radios retain power always. A reboot does not affect them at all. Power does though
And you'll be able to go to the latest 126.96.36.199 again after, I suspect.
Just had this happen with my C8. Never had issue before. Noticed things weren't working. Logged into hub and no Z-wave devices were listed in table. I rebooted hub and they came back.
But my question, what can cause this to happen?
Do you have cloud backup?
I've had this happen with my C-8.
I'm not sure rebooting was enough for me. I wound up doing a controlled shutdown and power cycle.
It happened around the same time as the 3 AM cloud backup-noticed when this old guy got up in the middle of the night to go to the bathroom.
It's been noted as an issue-they're looking into it but apparently it's sporadic and not repeatable, etc.
It only happened once for me, and for now, I've come to the conclusion that the cloud backup security is worth the risk.
I do have cloud backup. Went in and looked and there was a message the last cloud backup failed. Looking at the history it does a cloud backup on Fridays at 2 am. That would have been yesterday. Don't know for sure if it wasn't working all day or not. Sometimes we just don't do anything Z-wave related. It was yesterday we noticed the problem so probably related to the cloud backup failing.
A side affect. I just re-booted the hub and it started working again when the problem first started. However, I found I couldn't pair another device. I had a new device I was adding today and could not get it to pair. Finally I shutdown the hub, unplugged, then powered back up. After that my pairing worked just fine.