I think fuck-up my ADR config. I add the DR6 (SF7, BW250) to the maximum DR of the service. And some of my node switch to it successfully. But some don’t handle it and switch by default to SF12. When I see that I try to switch back with a maximum DR of 5 but Chirpstack don’t send new ADR frame. Are the frame re-try every some time if the sensors is not a the right DR? or only sent one?
PS: The sensors are not in a place easily accesible. So a reboot/rejoin is not possible (yeah, I fuck-up )
ChirpStack will stop trying after X failed attempts (by default 3):
# Max mac-command error count.
# When a mac-command is nACKed for more than the configured value, then the
# ChirpStack Network Server will stop sending this mac-command to the device.
# This setting prevents that the Network Server will keep sending mac-commands
# on every downlink in case of a malfunctioning device.
After fixing your config, you might want to try to increase that value. This way, ChirpStack should start sending mac-commands again to devices that failed for 3 times, which will reset the error counter. After all devices are back to normal, you can set this value back to 3.