Downlink Issue in Gateway Mesh Setup with ChirpStack - Uplink Working but No Downlink

Hi ChirpStack community,

I’m currently working on a gateway mesh setup using two Raspberry Pi 4 devices as a border gateway and a relay gateway. The setup is for the AS923 region, and I have recompiled the ChirpStack Gateway OS with the correct AS923 configuration.

The mesh uplink works perfectly, and my end device can send data through the relay to the border gateway, which then forwards it to the network server. However, I am encountering an issue with the downlink.

The system log shows that the downlink is being enqueued at the border gateway, but my end device does not receive the downlink. Below is a snippet from the system log:

Mon Sep 23 09:15:41 2024 user.info chirpstack-concentratord-sx1302[2351]: Frame received, uplink_id: 432133254, count_us: 3879112577, freq: 923400000, bw: 125000, mod: LoRa, dr: SF10, ftime_received: false, ftime_ns: 0
Mon Sep 23 09:15:41 2024 user.info chirpstack-gateway-mesh[4920]: Mesh frame received - [uplink_id: 432133254, freq: 923400000, rssi: -10, snr: 10.25, mod: [LORA - sf: 10, bw: 125000]]
Mon Sep 23 09:15:41 2024 user.info chirpstack-gateway-mesh[4920]: Unwrapping relayed uplink, uplink_id: 432133254, mesh_packet: [Uplink hop_count: 1, uplink_id: 81, relay_id: ff1e751a, mic: 0d1350ad]
Mon Sep 23 09:15:41 2024 user.info chirpstack-gateway-mesh[4920]: Sending uplink event - [uplink_id: 432133254, freq: 924400000, rssi: -41, snr: 13, mod: [LORA - sf: 7, bw: 125000]]
Mon Sep 23 09:15:41 2024 user.info chirpstack-mqtt-forwarder[5154]: Received uplink frame, uplink_id: 432133254
Mon Sep 23 09:15:41 2024 user.info chirpstack-mqtt-forwarder[5154]: Sending uplink event, uplink_id: 432133254, topic: as923/gateway/0016c001ff1e751d/event/up
Mon Sep 23 09:15:41 2024 daemon.warn dnsmasq-dhcp[1]: no address range available for DHCP request via br-lan
Mon Sep 23 09:15:41 2024 user.info chirpstack-mqtt-forwarder[5154]: Received message, topic: as923/gateway/0016c001ff1e751d/command/down, qos: AtMostOnce
Mon Sep 23 09:15:41 2024 user.info chirpstack-mqtt-forwarder[5154]: Received downlink command, downlink_id: 738518276, topic: as923/gateway/0016c001ff1e751d/command/down
Mon Sep 23 09:15:41 2024 user.info chirpstack-mqtt-forwarder[5154]: Sending downlink frame, downlink_id: 738518276
Mon Sep 23 09:15:41 2024 user.info chirpstack-gateway-mesh[4920]: Downlink command received - [downlink_id: 738518276 - [freq: 924400000, power: 16, mod: [LORA - sf: 7, bw: 125000], timing: [DELAY: 1], [freq: 923200000, power: 16, mod: [LORA - sf: 10, bw: 125000], timing: [DELAY: 2]]
Mon Sep 23 09:15:41 2024 user.info chirpstack-gateway-mesh[4920]: Sending downlink frame as relayed downlink, downlink_id: 738518276, mesh_packet: [Downlink hop_count: 1, uplink_id: 81, relay_id: ff1e751a, mic: c44d2d68]
Mon Sep 23 09:15:41 2024 user.info chirpstack-gateway-mesh[4920]: Sending mesh frame - [downlink_id: 738518276 - [freq: 924800000, power: 20, mod: [LORA - sf: 10, bw: 125000], timing: [IMMEDIATELY]]]
Mon Sep 23 09:15:41 2024 user.info chirpstack-concentratord-sx1302[2351]: Enqueueing immediate packet, downlink_id: 738518276, current_counter_us: 3879457646
Mon Sep 23 09:15:41 2024 user.info chirpstack-gateway-mesh[4920]: Enqueue acknowledged, downlink_id: 738518276
Mon Sep 23 09:15:41 2024 user.info chirpstack-mqtt-forwarder[5154]: Received ack, items: ["OK", "IGNORED"], downlink_id: 738518276
Mon Sep 23 09:15:41 2024 user.info chirpstack-mqtt-forwarder[5154]: Sending ack event, downlink_id: 738518276, topic: as923/gateway/0016c001ff1e751d/event/ack

1 Like