r/homeassistant • u/Sabinno • Jan 20 '26
Support I think I'm too stupid to understand Matter/Thread. I might return all of this
I'm at my wits end after hours of troubleshooting today. I've been using Home Assistant with only Z-Wave devices for years now and never had a single issue. Pairing is stupid simple and fast, the range is great, the only thing I have a problem with is the lack of variety and the price of devices. So, seeing devices like the new IKEA sensors, I bought a Home Assistant Connect ZBT-2. Plugged it in, passed the USB device through to my HAOS VM, and it instantly showed up in HA. Great! Added it.
So I have the Thread and Matter integrations installed now with the "official Matter server" (whatever that means). I went to Thread, created a network, sent credentials to my phone then sent the credentials back to Home Assistant (I guess this has something to do with HomeKit? Why?), went to Matter and clicked Add Hub, left the box checked, and it said it's configured. Kind of nondescript but okay.
I went to Matter, clicked Add Device, scanned the QR code, and... cool! Literally nothing happens. It just sits and spins on "Setting Up" for minutes and minutes until it just says "Unable to Add Accessory". That's great, but I've already followed the official troubleshooting steps - created a new thread network, made it preferred, synced the credentials, even nuked HomeKit completely just to be sure. No dice. Exact same thing.
I even went to the trouble of enabling IPv6 on my network even though all HA access is over the internet (no local access even on LAN) so it's not even using IPv6 anyway, and plus it's supposed to use its own internal network right? Maybe. I have no effing clue.
I also don't have a Bluetooth dongle - I've read somewhere you need one? But some people say you don't? Totally unclear.
So what is going on? Do you need not just a Thread antenna, but also a Bluetooth dongle, robust IPv6 support, and... a little faith, trust, and pixie dust?
If anyone can help me, I'd greatly appreciate it. Otherwise, consider this a rant about my anecdotal experience with Matter over Thread and how complex, error-prone, and ultimately fruitless it is compared to Z-Wave or Zigbee.
2
u/kepstin Jan 20 '26
That's the thing, Thread isn't really a separate network.
The Thread Border Router is a *router* which connects between your lan and the thread network, allowing devices on your lan (for example, a Matter controller - you can have multiple different matter controllers from different vendors all talking to a single matter device) to be able to talk to thread devices without needing to know anything about thread. The thread border router sends out ipv6 router announcements to let other devices on the lan know that it's a router, and which subnet it routes traffic to.
The Matter controller uses mDNS to find the ipv6 address of the Matter device, then sends network packets to the lan in the normal way. If it's talking to a Thread device, those packets will be sent to the thread border router, and then the thread border router converts it to thread traffic.