This may seem like an odd question (and to some extent, it is), but why does Matter over Thread stop working almost as soon as (but a little later than) Home Assistant running out of storage space on its volume?
Every other automation & integration set up in my Home Assistant keeps working (even if that means no new history being recorded), but everything Matter over Thread based fails.
Why? Is there any way around this?
Is the failure in
Home Assistant’s integration for Matter, Thread, or OTBR
OTBR
Matter JS server?
My does all ZigBee stuff keep working, but every single Matter over Thread device fails?
And why is this only after several hours of no-more-space? I can’t possibly see a good reason, especially when we consider everything else continuing to work as intended (except for new history data, ofc).
Comparing Zigbee and Matter over Thread like that is like compating the battery life on a window sensor with a mmWave sensor.
The mmWave sensor is far more complicated and will die at voltage levels that the window sensor will run fine with for months.
Matter and Thread is more complicated, but also give many extra features that the Zigbee for a lot able to provide.
One of those features is to have multiple Thread Border Routers and Matter servers running the same devices, which is part of the solution you look for, but the real issue here is really that you let it run out of space.
Space is a requires resource, just like ram, cpu, network and so on.
I had the same issue, and here’s what I found from AI: Matter over Thread relies heavily on a server‑side process that runs independently from the core Home Assistant system – and that process is extremely sensitive to storage space.
Think of Home Assistant core as the commander, and Zigbee devices as obedient soldiers. Matter over Thread devices, however, depend on a whole “communications staff” (including OTBR, Matter Server, etc.). When storage runs out, the commander is still there, but the staff is paralysed because it “can’t write files” or keep logs.
Why does Zigbee still work?
Zigbee is usually handled through ZHA (Zigbee Home Automation) or Zigbee2MQTT – these are often part of the core Home Assistant integration, or they communicate directly via serial ports. They don’t rely on separate containerised services that require heavy logging and frequent file writes. So even when history can’t be recorded, the core communication keeps running fine.