There appears to be a SiLabs bug that affects most EFR32MG1P based products on the market where the device will occasionally / rarely crash. After the crash, the device will no longer respond to APS frames, but will MAC ACK anything. Group/broadcast frames, including OnOff (0x6) still work fine. The device will still broadcast link status frames, but will report zero links.
Joined end device children to the crashed device will not find a new parent. They seem to think the parent is still working fine and will never find a new parent. Crashed router will not forward all frames from end devices. For example, a aqara motion sensor will send an occupancy attribute report which is lost but the lux attribute report is successfully delivered.
This bug has been confirmed by manup, one of the deconz developers and also by some of the Home Assistant ZHA developers. It seems more prevalent in large (100+) networks but even then devices can go for a few days to a few months before crashing.
I’m posting this here to just help spread the word – I’ve tried to put a few messages forward to the IKEA Embedded System Engineering group to notify them of the issue. This bug may be fixed in Emberznet 6.7.3 as these symptoms match perfectly, but the triggering conditions do not as ECC/SmartEnergy is not being used:
I know Chris is an excellent EZSP resource (thanks for the amazing sniffer, I use it daily) and didn’t know if he had any other thoughts he could share.