SX1301 Frequency is not within min/max gateway frequency - again

Hi Folks !
Sorry is this is an obvious question, I’m new to LoRaWAN and Chirpstack.
I have chirpstack gateway os base running on Raspberry Pi, talking to chirpstack on Ubuntu.
It’s working great for uplinks, I have a series a sensors and I’m able to see uplink data from them.
The problem is when I try to send downlink data, initiated from the “Queue” in the device page.

The log on the gateway indicates the frequency is not with the range, but for messages like confirmations, I think they go through ok.

This is a “queue” downlink request getting kicked out.

Nov 16 20:20:53 raspberrypi4 user.info chirpstack-concentratord-sx1301[558]: Enqueueing timestamped packet, downlink_id: 3779428626, counter_us: 49750860, current_counter_us: 49264384

Nov 16 20:20:53 raspberrypi4 user.info chirpstack-gateway-bridge[605]: time=“2022-11-16T20:20:53.065220326Z” level=info msg=“integration/mqtt: publishing event” event=ack qos=0 topic=us915_0/gateway/dca632fffe68c6d6/event/ack

Nov 16 20:20:53 raspberrypi4 user.info chirpstack-concentratord-sx1301[558]: Scheduled packet for TX, downlink_id: 3779428626, count_us: 49750860, freq: 926900000, bw: 500000, mod: LoRa, dr: SF7

Nov 16 20:20:59 raspberrypi4 user.info chirpstack-gateway-bridge[605]: time=“2022-11-16T20:20:59.256360007Z” level=info msg=“integration/mqtt: downlink frame received” downlink_id=3222812126 gateway_id=dca632fffe68c6d6

Nov 16 20:20:59 raspberrypi4 user.info chirpstack-gateway-bridge[605]: time=“2022-11-16T20:20:59.256799063Z” level=info msg=“backend/concentratord: forwarding downlink command” downlink_id=3222812126

Nov 16 20:20:59 raspberrypi4 user.err chirpstack-concentratord-sx1301[558]: Frequency is not within min/max gateway frequency, downlink_id: 3222812126, min_freq: 902000000, max_freq: 928000000

Nov 16 20:20:59 raspberrypi4 user.info chirpstack-gateway-bridge[605]: time=“2022-11-16T20:20:59.258010711Z” level=info msg=“integration/mqtt: publishing event” event=ack qos=0 topic=us915_0/gateway/dca632fffe68c6d6/event/ack

Nov 16 20:21:02 raspberrypi4 user.info chirpstack-concentratord-sx1301[558]: Frame received, uplink_id: 533447058, count_us: 58761036, freq: 903300000, bw: 125000, mod: LoRa, dr: SF7

Nov 16 20:21:02 raspberrypi4 user.info chirpstack-gateway-bridge[605]: time=“2022-11-16T20:21:02.563727968Z” level=info msg=“backend/concentratord: uplink event received” uplink_id=533447058

Nov 16 20:21:02 raspberrypi4 user.info chirpstack-gateway-bridge[605]: time=“2022-11-16T20:21:02.56416245Z” level=info msg=“integration/mqtt: publishing event” event=up qos=0 topic=us915_0/gateway/dca632fffe68c6d6/event/up uplink_id=533447058

Nov 16 20:21:03 raspberrypi4 user.info chirpstack-gateway-bridge[605]: time=“2022-11-16T20:21:03.062326209Z” level=info msg=“integration/mqtt: downlink frame received” downlink_id=2107833001 gateway_id=dca632fffe68c6d6

Nov 16 20:21:03 raspberrypi4 user.info chirpstack-gateway-bridge[605]: time=“2022-11-16T20:21:03.062592894Z” level=info msg=“backend/concentratord: forwarding downlink command” downlink_id=2107833001

Nov 16 20:21:03 raspberrypi4 user.info chirpstack-concentratord-sx1301[558]: Enqueueing timestamped packet, downlink_id: 2107833001, counter_us: 59761036, current_counter_us: 59263106

I added some debug to the rust module for SX1301, rebuilt the poky image (4.0) and verified that the frequency read by the concentratord is actually 0.

Here’s the debug from my build

Nov 16 20:40:41 raspberrypi4 user.err chirpstack-concentratord-sx1301[533]: Frequency is not within min/max gateway frequency, Freq: 0, downlink_id: 2974621569, min_freq: 902000000, max_freq: 928000000

It looks like at this point, the freq_hz is missing from the tx packet, before it gets transmitted.

Does anyone have any ideas I could follow up on before I dig deeper into the code ?

Many thanks !

OK, finding out more … the tx_info.frequency from the DownlinkFrameItem in downlink_from_proto is zero, which in turn means freq_hz is zero and causes the packet to not transmit.

Next, I’ll try to figure out why the DownlinkFrameItem has frequency set to zero.

Chirpstack-gateway-bridge is sending a zero frequency. This isn’t a concentratord problem after all.

Nov 17 01:24:42 raspberrypi4 user.info chirpstack-gateway-bridge[1065]: time=“2022-11-17T01:24:42.321677362Z” level=info msg=“backend/concentratord: forwarding downlink command” downlink_id=467200437 freq=0

I guess I’ll poke my nose into the gateway code and see if I can see why it’s sending 0 for freq.

gateway gets a 0 freq from mqtt.
Guess I need to poke my nose into chirpstack itself.

Nov 17 01:40:02 raspberrypi4 user.info chirpstack-gateway-bridge[1122]: time=“2022-11-17T01:40:02.302221762Z” level=info msg=“integration/mqtt: downlink frame received” downlink_id=1567680822 freq=0 gateway_id=dca632fffe68c6d6

Which versions are you using, on your server and which ChirpStack Gateway OS version?