Nest Wifi Routers not joining existing Threads network

[Xyzxyz]

I have a problem with my Nest Wifi Routers, where they refuse to join my existing Threads network. 

After investing in my first Matter over Threads smart plugs (Onvis S4) around 6 months ago, I successfully had them paired through the Google Home app. But I was quickly surprised by the extremely spotty connectivity, where they went offline for hours multiple times a day.  Around the same time, I started using Home Assistant, which detected 4 separate Threads networks accessible (named NEST-PAN-xxxx), instead of just one as I had anticipated, with my smart plugs all connected to just one of them (controlled by a Nest Hub). 

I've since factory reset my Nest Wifi Routers, my Nest Hub and my Matter over Threads devices multiple times, every single time I get 4 separate Threads networks and the plugs all connecting to the new network created by the Nest Hub. Lately I took a chance at getting an refurbished extra Nest Hub for my bedroom, and this one immediately joined the same Threads network as my other Nest Hub. But after factory resetting my network yet again, the same problem persists. The Nest Hub forms a single network, where all my smart plugs join, but my 3 Nest Wifi routers each creates their own separate defunct Threads network.

I have also since bought and installed an Home Assistant ZBT-2 Connect antenna that I flashed with the official OpenThreads Border Router firmware, and it immediately joined the network of my two Nest Hubs, which (finally) solved the connectivity problem of my smart plugs. But I still can't get my Nest Wifi Routers to join in on the fun, no matter how many factory resets I try and whatever tip I perform from old forum posts.

I have tried the following tips from forums, to no avail:

• Disconnecting my hardwired Ethernet backhaul during provisioning 
• Disabling IPv6 on my main Nest Wifi Router before adding the other Nest Wifi Routers back, both with and without wired Ethernet.
• Then again with IPv6 specifically enabled, both with and without wired Ethernet
• And finally, I also tried the often mentioned trick to clear data from Google Play Services on my phone.

And just as a quick heads up for anyone thinking about clearing app data for Play Services --- n e v e r -- e v e r -- do that! I mean it! You'll run into so many problems with your phone that you just wished you had it completely factory reset in the first place.

Right now, I'm totally out of ideas for how to solve this issue (which is a first for me, as a usually tech-savvy software developer professionally).

Any ideas on how to solve this? 

[AshleyB]

Hi @Xyzxyz,

Thank you for posting in the community. I’m sorry to hear you're having issues getting your Nest Wifi routers to join your existing Thread network, resulting in multiple separate networks rather than a unified mesh. I understand how frustrating this can be.

I appreciate the detailed information you've shared regarding the extensive troubleshooting you've already performed, including factory resets and adjusting IPv6 and Ethernet backhaul settings. I'm happy to assist you with this.

To help me investigate further, could you please provide the following details:

• What is the current status light on your devices?

• Are you using a modem/router combo?

• What is the status of the Nest Wifi routers in the Google Home app?

Keep me posted; I'll be waiting for your response.

Best regards,

Ashley

[Xyzxyz]

Hi @AshleyB 

The status lights are all off, but they do not indicate an issue (flashing yellow). I tested briefly turning on status lights and they are all white.

I have a fiber terminator which is connected to the WAN port of my main Nest Wifi Router, running in NAT (standard) mode.  All of my Wifi points are running in Bridged mode, and all status lights are normal. All but one of them are connected to the LAN port of my main Nest Wifi Router via a switched Ethernet backbone. Only one Wifi point is connected wireless.

My Nest Wifi Routers:

1. Main Router: Nest Wifi router H2D, software version: 14150.883.17
   • LAN IP: 192.168.1.1
   • Status: "Online and connected to 7 Wifi points // Your Wifi router is online and everything looks good."
2. Nest Wifi router H2D, software version: 14150.883.17
   • LAN IP: 192.168.4.31
   • Status: "This Wifi point has a good connection"
   • Connection type: Wired
3. Nest Wifi router H2D, software version: 14150.883.17
   • LAN IP: 192.168.4.29
   • Status: "This Wifi point has a good connection"
   • Connection type: Wireless
4. None of the other Wifi Points are Threads-capable (4x Google Wifi Router AC-1304 v14150.376.32+ 1x Google Wifi Router GJ2CQ v14150.376.32)

[AshleyB]

Hi @Xyzxyz,

Thanks for replying; I appreciate all the detailed information you shared. It was very helpful. It will be necessary to follow some troubleshooting steps to resolve the issue you are experiencing with your Nest Wifi routers not joining the existing Thread network. Please follow these steps:

• Use the Google Home App: Ensure your Nest Wifi routers are set up in the same "Home" as your other devices. Google tries to merge Thread networks automatically for devices within the same "structure."

• Check for "Matter" Pairing: If you are trying to bridge an Apple Thread network to Google, use the "Link Apps & Services" or "Share via Matter" option in your original app to generate a pairing code that Google Home can use to "see" the network.

Keep me posted; I'll be waiting for your response.

Best regards,

Ashley

[Xyzxyz]

Sorry for the late reply. I was a bit dejected by your instructions and lost my hope there for a while. I understand you're trying to help, but those steps felt on par with being asked if I had plugged in the power cord.

But anyway: 

• Yes. The Nest Routers all have joined my "Home" in the Google Home App, as I already wrote previously. This is not a problem with the Wifi capabilities, the Mesh/Roaming backhaul communication or Ethernet routing. It's purely that each of my four Nest Wifi Routers fails Thread provisioning and creates/retrieves incorrect Thread datasets, thus preventing them from joining my Thread network controlled by my two Nest Hubs.
• No, There's no Apple protocol over Thread involved. I'm not trying to bridge or pair anything. Pairing Matter devices to my Thread Network works flawlessly. I have successfully joined four Onvis S4 Smart Plugs as Thread Routers (N.B.: Routers -- not Border Routers), one OpenThread Border Router using a ZBT-2 antenna and two Thread Endpoints (Bilresa wall switches by Ikea). It's just that every one of my four Nest Wifi Routers refuses to join this Thread network, likely because of faulty Thread Dataset/Credentials.
  

[e-ra]

Hey @Xyzxyz,

I'm also having a similar issue where my devices intermittently disconnect.

When you go to home assistant, are you seeing something like this?

 That's 1 Thread Network but 4 separate border routers.

I'm actually trying to split the networks to try and isolate the issue (i.e is it an issue with the Google Nest Routers?) but I can't work out how to split them.

Have you tried a building a Thread Network that doesn't include Nest Routers at all? e.g using the ZBT-2 and just the smart plugs?

E-Ra

[Rapier]

Dear Google specialist. Please help us. This is "thread network" for smart home devices we are not talking about wifi mesh. Please note this and give relevant answers or report it to the correct dev team. 

[herman33]

Each Nest Wifi unit can create its own Thread network, and Google doesn’t reliably merge them. That’s why you’re seeing multiple nest pain networks. Resets and tweaks won’t really fix it (as you’ve already noticed).

The good news: your setup with the Nest Hubs + the ZBT-2 is actually the right way to handle it. That’s why everything became stable after adding it.

Best way forward:

Keep using the Nest Hub / ZBT-2 as your main Thread netzwerk
Ignore the extra networks from Nest Wifi (they’re harmless)
Don’t waste time on more resets , it won’t change this behavior

[Rapier]

Thanks for your answer. 

In my case the wifi routers do not merge to anything but their wifi points coming with them merge to ikea drigera and google tvstreamer happily. 

I wish I could at least turn off thread on the routers so that my main network does not need to fight against 2 other networks created by the routers.

I gave up as you said already since there is no way to fix this I wish google made an option to move devices to the network... Anyway or turn the tread network off for those.

Currently thread network is wonky where those routers are. I need to add more powered thread devices to fight those routers. For the rest of the house I never had any problems with tread devices being less responsive or missing responses. 

[Xyzxyz]

Nah, I simply cannot give up.

Partly, because I really need  more Border Routers in order to maintain decent coverage in my 4+ floor house over 4 separate wings/sections with interior brick walls clad in double layers of lath and plaster with a steel mesh as a bearer for the plaster. Every room is effectively its own shielded Faraday Cage. 

But also because OpenThread Border Router is not sufficiently stable and reliable yet. Every few weeks it refuses to route Matter traffic into the Thread network, despite apparently being connected.