[Solved] Zigbee Instability is back!


A traceroute utility would be fantastic.

I've got 43 plugs moved back to HE tonight, there are no other Zigbee devices on my hub at the moment. I'm not even going to take time count how many are randomly unresponsive, but it's between 1/2 and 1/3 don't respond to commands, and only randomly report events.

I hope really this is a bad stick because I'm unable to replicate on other platorms. XCTU shows a clean mesh with no unreachable devices.


It’s been a quiet couple days on this thread so here’s an update for those following.

Yesterday was like a second Christmas. I received the second hub and radio sticks, the extra ST v4 Plugs, and the ConBee for zigbee sniffing.

I immediately went to work on the new hub after dinner. The plan is to move only Zigbee devices to the second hub in the short term so the current stable ZWave mesh isn’t affected.

I decided to be quite unforgiving to the new hub by connecting as many devices in the time available. That included 43 SmartPlugs (did not include Iris ZWave radios at this time) and 15 battery powered devices. At the end of the night the mesh was still stable.

This morning there was one SmartPlug that failed to respond. This time a 4th Gen SmartThings plug. Had to put the hub into inclusion to get it back.

I took a half hour before leaving for work and blew through reconnecting another 17 devices, all battery powered. The mesh was tested a half hour ago and a different ST v4 plug didn’t respond. A simple click on configure fixed that. All other devices were responsive and reporting.

I’m not going to declare victory yet. In my initial transition to Hubitat it took several days for the instability to creep in. There is however one encouraging sign that is unique this time around. Zigbee device pairing is significantly faster with most devices connecting in 10-30 seconds. On the other hub and stick, 30 seconds was fast with most devices taking a minute to two.

There’s more to come tonight as I plan to continue my rapid rebuild of my Zigbee device to attempt to stress the mesh into breaking.




A lot of people are following your progress and rooting for you on this one.


This was not a good sign. Very unusual, unless the device is very far from the hub with no repeaters.


Quick question. Any idea why the time is off on the replacement hub? The timezone is set correctly, and the time setting shows the correct time, but all event times are 5 hours ahead.

Hub Details
Hubitat Elevation™ Platform Version
Hardware Version
Rev C-4

Default Text To Speech (TTS) Voice

Current Hub Time (as of last page load)
2019-01-23 5:20:40 PM EST


The standard fixup is to reboot. It's like it sets time before you do the setup and then a reboot causes it to use the setting. You may not want a reboot in the middle of your test.


I had a feeling that was the case. Thanks!


Once you reboot, don't forget that any current events you are looking for in an event page will be sorted lower than earlier events, at least until you pass that 5 hour offset. That's thrown a few people off who are checking to see if events happened.

For example:

  1. Light on 2:30pm EST (logged as 7:30pm)
  2. Light off 3:30pm EST (logged as 8:30pm)
  3. Light on 4:00pm EST (logged as 9:00pm)
    ** reboot hub **
  4. Light off at 4:15pm EST (logged as 4:15pm)
  5. Light on at 5:00pm EST (logged as 5:00pm)

Events page will be sorted in descending order as follows:

Light on at 9:00pm (event 3)
Light off at 8:30pm (event 2)
Light on at 7:30pm (event 1)
Light on at 5:00pm (event 5)
Light off at 4:15pm (event 4)


Thanks for the tip I’ll keep that in mind during testing.. It’s unfortunate that the information isn’t stored in UTC and manipulated upon display.


I had made already that suggestion as well. Even from a support perspective should be better I would say :wink:


I'm starting to see consistent 3-7 minute pairing times Iris contact sensors now..

Edit: As I moved on through the evening, it appears as if the slow pairing has been limited primarily to the Iris Contact Sensors. I did observe some weird behavior connectingrandom devices tonight. On three seperate occasions one or more smartplugs briefly toggled off and on during the pairing process. I've never seen that occur before on any platofrm.


Are saying you were pairing another device and some plugs toggled off and on?

If yes, I never seen that


That is exactly what I witnessed. It happened only during inclusion each time.

Anyhow, at this point there are about 33 Zigbee devices remaining to be connected. The mesh is still stable, but I've decided to wait until Saturday before declaring an official resolution.

Of course once I do that, I will need to deal with the ~120 Z-Wave devices.....


I am so glad to hear that you're making progress. Thanks for the updates! We're all cheering for you to have a win!


I do feel like progress is being made which is a good thing.

I added another 8 plugs and an XBee3 this morning after my last post. That should give the mesh time to settle down before connecting the remaining battery-powered devices tonight. That brings the connected plug total up to 51.

Things are holding in a stable state right now.


This is great news! (knock on wood)


Could this be the same as problem as noted in this post https://community.hubitat.com/t/odd-problem-with-zigbee-bulbs


I feel your pain, over the last 72 hours I have had about 10 devices go AWOL, after being stable for over a month. All I did was move my HE hub about 4 feet to the right to a wall mount.
I wish I knew the radiation pattern for the husbzb-1 stick to optimize my placement/orientation.
I did find this info for my ST hub but couldn't locate for our stick.


Chances are it’s less about pattern and more about polarization. These devices usually use onnidirectional antenna traces on the circuit board. The polarization is dependent on the orientation of the PCB. If for example your stick was originally vertical but is now horizontal, the polarization has changed.

You mention a wall mount. Another factor is wall construction. If you mounted it on a wall containing foil insulation that will attenuate and also reflect the signal. If the wall has metal studs, metal HVAC ductwork, or is filled with copper/cast iron pipes, those things will affect the radiated signal strength and pattern too.