My C4's entire Zigbee mesh died overnight (on 2.2.4)

What the heck, device activity showed multiple zigbee devices had dropped off overnight. Looked at settings and discovered the entire zigbee network was offline. :angry:

Ok so suitably pissed (who wants to rejoin every device on a Sunday) I reboot the hub and it goes offline and doesn't reboot. Light's still blue, so I wait..... . Ok so now everything really is dead - no diagnostic tool. Which leaves me no option but to nuke the hub by pulling power.

So is there a correlation between this event and 2.2.4? I don't know but it's never happened before. (PS nothing new added to the hub during this period other than to update a couple of simple automation rules using 1.1)


Phew, nearly all devices back online :relieved:

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Check zigbee details, did the PAN ID change?
If so not all devices might rejoin

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Lol totally forgot in the heat of things. Will keep track of the ID from here on in!

This sounded like your hub crashed hence the Zigbee radio went offline. I would look in the past log to be sure your database is not corrupted otherwise it will happen again.

It couldn't have crashed as it was still functioning (could access the UI just fine just no zigbee.

I seem to remember many people complaining that this would happen when the hub overheats. Is it in a well ventilated area?

Might be worth trying a backup and restore to see if that makes a difference.

Maybe, but I haven't seen any widespread reports on here. Hopefully it is just a coincidence.

Yes it's been in the same spot since day 1 with plenty of space around it

I'll do that once the bulk of the migration to the C7 is complete.

You're probably right. In any case I'm eventually turning it into a glorified repeater in another part of the house!

I've noticed a couple of times after a reboot that a hub sometimes will briefly show a Zigbee offline message. It seems to clear up though. Today at my clients on a C-7 I did a shutdown, pull plug, restart after funky z-wave inclusion and when it came back up the zigbee went offline, no devices etc - I don't HAVE any zigbee devices on that hub yet. I got it back by going to the Zigbee details page and bringing it offline then putting it back online again. This seemed to work okay. I did end up rebooting a bit later and everything was fine.

funky :unamused:

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I have noticed similar "funky" activities from my hubs.

A shutdown, and wait, and restart seems to have cured whatever was ailing it.

Very strange, but everything is back to working.

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There was a bug with zigbee "last activity" timestamp getting messed up when hub time changes during a reboot. This has been fixed a few versions back, though, please let me know if you're on the latest version and it's still happening.

We also know that Zigbee radio can overheat and go offline - with any firmware version. I can take a look at a particular hub if that's what's happening.


I see has a bug fix for C4s. Am applying it now and will report back if things are ok or otherwise.

Ah crap. Zigbee radio just went offline. Reboot did nothing so pulled the plug again. This time the C4 is refusing to boot up at all, blue light is on.

Left it unplugged for a while but still nothing. Powered up with no zwave/zigbee sticks, finally booted after a few tries. Twice in 2 weeks! @gopher.ny how can I diagnose further?

Hey gopher, so this is happening with the Nortek external radio also? Or mostly with the c5 with internal zigbee radio

Internal radios appear to be affected most since they share the circuit board.

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