Join issue, dev-nonce errors, more lorawan frames than device data


We have a setup spanning about 8 floors in a building using two gateways. I don’t think the fact we use two gateways is relevant to the issue, but I’m mentioning it since I’m not 100% sure.

We have 4 devices that used to work but now can’t seem to join anymore. The devices are Ursalink UC11-T1.

The “Lorawan Frames” tab shows Join requests incoming with varying freq and SF. They seem to come in bursts, like 10 in 3 minutes, then nothing for a few hours. Not sure whether the device itself tries by bursts or whether this is due to RF range issues. The “Device Data” shows dev-nonce errors with a much lower frequency. About 10 in 10 days, irregularly.

I purged the dev-nonce for those sensors in the DB, to no avail. I discovered afterwards the “Disable frame-counter validation” checkbox. IIUC, this is meant to ignore dev-nonce. I unchecked it for the devices but I still get dev-nonce errors.

My questions are

  • Why do I get dev-nonce errors if I erased dev-nonces in DB and disabled frame-couter validation?

  • How come I get more (Join Request) messages in “Lorawan Frames” than (dev-nonce error) messages in “Device Data”?

  • What can I do? (Remote building but we might have physical access next week so acting on the devices could be a last resort option.)

BTW, I installed Chirpstack a while back and have been applying updates since then without really using it. Coming back to it recently, I discovered a few nice features (new plots, “Device data” and “Lorawan frames” being recorded so that the display isn’t empty when opening the tab, plus I guess all those internal changes I don’t see.) Congratulations and thanks for these.