Unable to add a second Connect ZBT-2 as a standalone Thread Border Router

I’ve been trying to add a second ZBT-2 device to my HA without success. I need a standalone Thread Border Router for an outbuilding on my property. I’ve been reading dozens of different instructions, but with no luck. Last night I had to restore from backup because it’s screwed up everything in my HA that had to do with Matter devices. There is something I’m missing, and it’s probably simple, but I’m starting to pull out my hair in frustration.
If I didn’t have so many smart devices, I’d pull the plug and start from scratch, but that’s more than a weeks worth of work.
I love HA but all the help docs always leave something out and I’m new to the HA device and apps.

HA OTBR app is just a single instance, so it can only handle one ZBT-2. HAOS can only support one app instance of the OTBR (although there are hacks that can be done to spin up a second OTBR app instance but I don’t recommend it).

Having said that, I believe the HA Core OTBR Integration and Thread Integration can handle multiple OTBR instances so with one HA System, you should be able to manage an OTBR locally and one remotely.

A few (perhaps obvious) choices:

  • A second HA system@outbuilding running HAOS with OTBR+ZBT-2. Although you can control the OTBR either from the second HA instance or the first, I would recommend it be completely managed by the second HA system.
  • Some other computer/machine running a Docker version of OTBR+ZBT-2.
  • An Apple/Google device running as a TBR.
  • ESP Based - You can search the forums about using an ESP(s) to create a OTBR.

Another choice I have seen lately is a SLZB-xU with latest SLZB-OS firwmare which can now also run as a standalone OTBR on-device.