Trying to queue downlinks via Python from external server

I am attempting to follow the Python downlink queueing example here:

My server’s api page is accessible via:


(no special port needed)

The example shows how to queue a downlink assuming the example is ran on the same host instance as the server. I’m attempting to queue a downlink from a host external to the Chirpstack server.

So - I modified the example code as follows - I obviously redacted my server address and API key :wink:

import os
import sys

import grpc
from chirpstack_api.as_pb.external import api

# Configuration.

# This must point to the API interface.
server = "redacted_server_address"

# The DevEUI for which you want to enqueue the downlink.
# dev_eui = bytes([0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01])
dev_eui = bytes([0x00, 0x25, 0xca, 0x00, 0x00, 0x00, 0x01, 0xeb])

# The API token (retrieved using the web-interface).
api_token = "readacted API token"

if __name__ == "__main__":
  # Connect without using TLS.
  channel = grpc.insecure_channel(server)

  # Device-queue API client.
  client = api.DeviceQueueServiceStub(channel)

  # Define the API key meta-data.
  auth_token = [("authorization", "Bearer %s" % api_token)]

  # Construct request.
  req = api.EnqueueDeviceQueueItemRequest()
  req.device_queue_item.confirmed = False = bytes([2, 2, 20, 12, 2, 19, 33, 31])
  req.device_queue_item.dev_eui = dev_eui.hex()
  req.device_queue_item.f_port = 10

  resp = client.Enqueue(req, metadata=auth_token)

  # Print the downlink frame-counter value.

Attempting to execute the code fails:
ubuntu@ip-172-31-35-174:~$ python3

Traceback (most recent call last):
  File "", line 36, in <module>
    resp = client.Enqueue(req, metadata=auth_token)
  File "/home/ubuntu/.local/lib/python3.6/site-packages/grpc/", line 826, in __call__
    return _end_unary_response_blocking(state, call, False, None)
  File "/home/ubuntu/.local/lib/python3.6/site-packages/grpc/", line 729, in _end_unary_response_blocking
    raise _InactiveRpcError(state)
grpc._channel._InactiveRpcError: <_InactiveRpcError of RPC that terminated with:
	status = StatusCode.UNAVAILABLE
	details = "failed to connect to all addresses"
	debug_error_string = "{"created":"@1607197345.168422894","description":"Failed to pick subchannel","file":"src/core/ext/filters/client_channel/","file_line":4166,"referenced_errors":[{"created":"@1607197345.168419511","description":"failed to connect to all addresses","file":"src/core/ext/filters/client_channel/lb_policy/pick_first/","file_line":398,"grpc_status":14}]}"

Has anyone been able to queue a downlink from Python?


hi! Could you solve this??? Im trying the same: i have all the instances of chirpstack (Bridge+NetworkServer+AppServer)running in RAK2245 and my own server running my dashboard on the cloud. I want to send downlinks from my server to the GW considering that the instances run in different IPs and maybe the IP on the GW could change (its not a static ip).