Multicast: No downlink path available

End Devices (Nodes)
1

I have created the multicast device in v3 but when I schedule multicast downlink it will show below error

no downlink path available

How can I send a schedule multicast downlink?

2

@All

Does anyone know how to send Multicast Downlink from v3?

3

same issue here.

I belive that this is due to the fact that the NS does not not know which gateway to use, so it is needed to be specified somehow.

However, even following the instructions given here https://www.thethingsindustries.com/docs/devices/multicast/ , I can’t manage to schedule a downlink

in the mutlicastgroup, under “live data” i cannot even see any message when publishing this json

{
   "downlinks":[
      {
         "frm_payload":"/jIyMhE0NDQ0NA==",
         "f_port":42,
         "priority":"NORMAL",
         "class_b_c":{
            "gateways":[
               {
                  "gateway_ids":{
                     "gateway_id":"eui-xxxxxxxxxxxxxxxxxx"
                  }
               },
               {
                  "gateway_ids":{
                     "gateway_id":"mygatewayid"
                  }
               }
            ],
            "absolute_time":"2021-06-28T21:23:00Z"
         }
      }
   ]
}

the topic used is:
v3/myapplicationid@ttn/devices/multicastgroupid/down/push

I’m pretty sure that the topic is correct, becasue when I publish this JSON, whithout the gateway information

{
  "downlinks": [{
    "frm_payload": "/jIyMhE0NDQ0NA==",
    "f_port": 42,
    "priority": "NORMAL"   
    }
  }]
}

I got the same error message that i receive from the console (no downlink path available)

4

I am also getting the same error when trying to send downlink with multicast device. I am getting “no downlink path available” message. I am trying to publish below JSON in JSON-box of downlink message:

{“downlinks”:[{
“frm_payload”: “vu8=”,
“f_port”: 200,
“priority”: “NORMAL”,
“class_b_c”: {
“gateways”: [
{
“gateway_ids”: {
“gateway_id”: “ttn-gw-id”
}
}
]
}
}]
}

I hope I am not making a mistake here. Kindly let me how can I send multicast downlink.

5

I have the same problem when I am using stack Community Edition. Then I ran TTS locally and it works correctly.
How to solve it and make it working with TTN Community Edition?

6

Hello, I have the same problem: “error:pkg/networkserver:no_downlink_path (no downlink path available)”.

I have an end device based on NUCLEO-WL55. LoRaWAN Specification 1.0.3. Class C.
The gateway I connect to is TBMH100.

I created multicast group in cloud.thethings.network (LoRaWAN ver 1.0.3, ABP&Multicast). I got the Device address of the group and used it as McAddr for end device McGroupSetupReq.

I send McGroupSetupReq command to the end device according to the LoRaWAN Remote Multicast Setup v1.0.0 (the firmware in my device supports v 1.0.0). Ans is OK.
Then I checked the multicast status by McGroupStatusReq command. The created multicast group is in the list in the answer. This shoudl by ok.

I tried to downlink a message to my multicast group and i got no_downlink_path error. I also tried downlink by JSON with defined gateway_id according to thethingsindustries multicast (gateway_id, absolute_time and coma correction).
Still the same error.

I have read this is probably caused by the network server not knowing which gateway to use, and the end device have to communicate first (eg uplink OTAA…) for the network server to know which gateway to use. But the group is an virtual End device in cloud.thethings.network.

Pleas, does enybody know how to run multicast in cloud.thethings.network?
Let me know if I missunderstand something Im new in LoRa.

7

Sorry to add useless +1 spam. But seriously, this is broken an no reply within 1 year?

8

:frowning: quote=“kwinz, post:7, topic:47410”]
this is broken an no reply within 1 year?
[/quote]

Don’t know if it’s broken, but no reply in 1 year on the TTN community forum means that no other (volunteer) community member has replied to this topic. So not much to conclude. Could be another thread has a solution. But before you start using the search, I don’t recall any threads that talk about a solution. But that doesn’t mean it’s not working as no one ever posts what works or a how to anymore :frowning:

If you think it’s broken and want some considered input, post LOTS of details.

9

Do you provide gateway ids and absolute time to tx the packet to the api as shown In the docs?

1 Like
10

@kwinz did this work for you?

11

hey man
have you fix this problem ?
I have 2 lorawan gw(named A and B),using AS923-2-NDT
i have build a multicast device
then I use mqtt client login and send multicast msg ,if the gateway_id is A’s ID ,work fine ,multicast msg can downlink from gw A
but when i change to B’s ID , I got this err

"error":{"namespace":"pkg/networkserver", "name":"fixed_paths", "message_format":"invalid fixed paths set in application downlink", "code":3}}}

I dont kown why ,can you help me

12

by the way , the gw A and B all online , and gw B can recv lorawan end device msg

13

Hi, can you share the json that works for gateway A. I got the same error “No downlink path available” when trying to send a multicast msg, even though I specified the gateway_id in the json. Thanks