Sensor not joining?

ChirpStack Application Server
1

Hi,

We have a Sensor in chirpstack that keeps sending data fron frame counter 0 to 8. After that, it gives up and sends a new join and creates a new devNonce after a couple of minutes.

It repeats this pattern and does not seem to completely join. We’ve tried restarting the sensor, removing it from Chirpstack and adding it again, clearing devNonce, and disabling frame counter validation. It just keeps on going like this and we have no idea of what could be wrong.

I’ve tried looking for already existing cases but haven’t really understood the solution or if it’s even the same problem. Any idea?

Thanks in advance:slight_smile:

2

Could this be the case if a sensor is for example configured to send confirmed payloads while gateways/broker expects unconfirmed? Because that is the only difference that I can see between this sensor and our other ones.

3

could you please provide more details like what sensor are you using? some logs.

4

It is called Marine Environmental Minimoose Buoy, Sensecap. But it’s not that common from what I know.

5

Device data:

time:null
timeSinceGPSEpoch:null
rssi:-108
loRaSNR:-16
channel:4
rfChain:0
board:0
antenna:0
latitude:0
longitude:0
altitude:70
source:“UNKNOWN”
accuracy:0
fineTimestampType:“NONE”
crcStatus:“CRC_OK”
modulation:“LORA”
bandwidth:125
spreadingFactor:12
codeRate:“4/5”
polarizationInversion:false
adr:true
dr:0
fCnt:8
fPort:18
objectJSON:
confirmedUplink:true
publishedAt:“2025-04-02T06:24:52.965017903Z”

Lorawan frame:

power:14
modulation:“LORA”
bandwidth:125
spreadingFactor:12
codeRate:“4/5”
polarizationInversion:true
board:0
antenna:0
timing:“DELAY”
delay:“1s”
mType:“UnconfirmedDataDown”
adr:true
adrAckReq:false
ack:true
fPending:false
classB:false
fCnt:8
fOpts:null
fPort:null
frmPayload:null

6

I must apologize. I think this is a false alarm. This sensor is sending data and at the same time having this issue so it might not even be an issue that it renews its sessions