In chirpstack, How can I reset the code counter like fCnt ?
You can disable f_count verification in the device settings. Disabling, letting the device uplink once, and then re-enabling would allow Chirpstack to re-align with the devices f_count.
Thank you for your response.
Do you mean that we cannot reset Fcnt directly from within ChirpStack, and we need to restart the connection and ask the node to send a new join request?
No, disabling fcount will not require a new join-request. I was just saying that if you disable and re-enable f_count verification it will not flush the current f_count from Chirpstack memory.
You must disable it in the devices page in Chirpstack, let the device uplink once (not a join) so Chirpstack gets the updated f_count without discarding the packet, then re-enable it. This will re-align Chirpstack with the f_count of the device.
Do you mean devNonce though? If so you can flush devNonces from the device’s “activation” tab. It’s just a clickable button.
To reset the frame-counters, you could use the Activate API call. For OTAA devices it works the same as for ABP. It is mostly intended for migrating OTAA devices from other LNSes to ChirpStack.