Zigbee Network Health

I’m trying to figure out how a Zigbee Network maintains its health. My situation is Smarthings Hub V2, numerous Smartthing Devices, Sonoff Devices, Tradfi Repeaters.

I have a few Sonoff devices(SNZB-02, 04)keep going offline. In troubleshooting I keep looking at Device Route. Sometimes it shows via the repeaters and this am it was offline again. Looked at the Route and the device was direct to the hub. Found this odd as the nearby repeaters were all online.

My question is how do I troubleshoot? Do Zigbee Networks continue to change the route on its own?

Yes they maintain the routing and there is no way to (nor do you want to) manage it.

If those are direct routing at times and falling off.

  1. how far away are they from the hub
  2. what is the Zigbee channel for your hub?
  3. what wifi channel(s) is/are yiur wifi access points / routers using for thier 2ghz network (and channel width if you kniw it)
  4. have you recently moved your hub OR any wifi gear OR any USB3 hard drives?
  1. 30ft but have a Tradfi repeater midway

  2. Channel 20

  3. Wifi Channel 9

  4. No changes to Wifi Hardware

Do cordless phone operate in the 2ghz band? Could that be an issue?

1 Like

Your Wifi Channel is the likely culprit

This is how your WiFi router sees the channel spectrum:

for nine it’ll sit just a hair to the right of the valley between 6 and 11.

This is how your Zigbee radios see the same spectrum:

See the problem?


WiFi Channel 9 and Zigbee Channel 20 are right on top of each other, so very not good. :disappointed_relieved:

In addition, Wi-Fi channel 9 is not one of WiFi’s three nonoverlapping channels, many Wi-Fi routers won’t even give you that choice. Typically you have a choice between Wi-Fi channel 1, 6, and 11. If you were previously forced to choose Wi-Fi channel 9 because of other network interference issues, then you’ll need to find out the specifics of those as they might be an issue for zigbee as well.

The easiest choice to avoid zigbee/Wi-Fi interference would be to use channel 11 for both of those, as they are actually quite far apart in the band.


…unless EVERY SINGLE neighbor you have is on WiFI 2Ghz - Ch1… grumble grumble grumble…

1 Like

Some models do, and it could definitely be an issue.

To be honest, pretty much anything except Bluetooth operating in the 2.4 GHz band can be a problem for zigbee as zigbee is used in home automation, because zigbee is a very low power protocol, and it just gets drowned out. :scream:


Awesome infomation, I’ve changed my wifi to Channel 11. Testing to continue.


mind you - it wont be immediate - it may take a while for your network to rearrange itself. When my Wifi router stomps my zigbee (and the reason I scrapped it) After I figured it out and fixed it - it would usually take about two hours to come back. Don’t even think about testing for 30 mins.

Think ‘freight train’ not ‘sportscar.’ Or Harley-Davidson Road Glide CVO vs. a 'Busa…

Did you scrap your zigbee? Move to?

NO I scrapped the WiFi router and moved to new WiFi6 gear.

I wanted to scrap the neighbor’s router(s) - but something about breaking and entering, destruction of property and a few other annoyances changed my mind.


Just an update…after changing my wifi off of channel 9 all appears to be working. No drop-offs.