Hi Chirpstack community,
I’m currently trying to setup Chirpstack on my Raspberry Pi 4 and RAK2287 as concentrator (connected through a PiHAT on SPI). I want to test the FUOTA capability, that was working for me in the past on a Raspbian and FUOTA as the experimental feature. Now I wanted to try the Chirpstack OS, I setup a clean install on an SD card, even established a basic communication with an end node.
However when it comes to FUOTA, the campaign is set well, node is ready to receive in Class C, fragments are enqueued using the multicast group, but they never reach the gateway. Digging into the logs I see:
Tue Sep 2 11:23:31 2025 user.info chirpstack-mqtt-forwarder[3122]: Sending downlink frame, downlink_id: 2187393511
Tue Sep 2 11:23:31 2025 user.err chirpstack-concentratord-sx1302[4223]: Convert downlink protobuf to HAL struct error, downlink_id: 2187393511, error: gps_ref_valid = false
Tue Sep 2 11:23:31 2025 user.err chirpstack-concentratord-sx1302[4223]: Handle downlink error, error: gps_ref_valid = false
Tue Sep 2 11:23:31 2025 user.info chirpstack-mqtt-forwarder[3122]: Received ack, items: [], downlink_id: 2187393511
Since this error I tried changing the configuration, enabling/disabling the GNSS, I even tried older versions of the Chirpstack OS, but the error is the same. It is not strictly related to FUOTA, just a simple multicast shows the same problem (message enqueued, but never sent, raising the errors). Googling this error didn’t help either as there are only few links that are unrelated to my issue, so I decided to post it here.
Did I miss some configuration steps in the concentrator? Or where the issue could be?
Thanks in advance for any help.
Regards,
FilipS