Adding in US915 Sub-Band 2 to v4

I want to add in channels 8-15 and 65; Sub-Band 2. I currently am using 0-7, 64 successfully for a test.

I have a few questions.

Will the Lorawan gateway have issues with new bands added on the gateway server? I set the gateway up for sub-band 1.

For updating the: /etc/chirpstack-gateway-bridge/chirpstack-gateway-bridge.toml

I currently have the following to support 0-7;64

[integration.mqtt]
event_topic_template=“us915_0/gateway/{{ .GatewayID }}/event/{{ .EventType }}”
command_topic_template=“us915_0/gateway/{{ .GatewayID }}/command/#”

Would I just add additional lines for all bands? IE 915_1 through 915_7?

The ChirpStack Gateway Bridge does only support a single region. However, you could modify your region to support 16 channels (if your gateway supports that and is configured for this).

The us915_0 maps to the MQTT topic prefix of the region configuration. See:

Are you saying to modify the us915_0 with the additional channels up to 16?

IE: Add 8 the appropriate 8 channels as defined here?

[[regions.gateway.channels]]
  frequency=902300000
  bandwidth=125000
  modulation="LORA"
  spreading_factors=[7, 8, 9, 10]

@brocaar sorry, I am just not following here. Not fully understanding the process.

This would be a minimal config example:

[[regions]]
  id="us915_0_1"
  description="US915 (channels 0-15 + 64 & 65)"
  common_name="US915"

  [regions.gateway]

    [regions.gateway.backend]
      enabled="mqtt"

      [regions.gateway.backend.mqtt]
        topic_prefix="us915_0_1"
        server="tcp://$MQTT_BROKER_HOST:1883"

    # Channel 0
    [[regions.gateway.channels]]
      frequency=902300000
      bandwidth=125000
      modulation="LORA"
      spreading_factors=[7, 8, 9, 10]

    # Channel 1
    [[regions.gateway.channels]]
      frequency=902500000
      bandwidth=125000
      modulation="LORA"
      spreading_factors=[7, 8, 9, 10]

    [[regions.gateway.channels]]
      frequency=902700000
      bandwidth=125000
      modulation="LORA"
      spreading_factors=[7, 8, 9, 10]

    [[regions.gateway.channels]]
      frequency=902900000
      bandwidth=125000
      modulation="LORA"
      spreading_factors=[7, 8, 9, 10]

    [[regions.gateway.channels]]
      frequency=903100000
      bandwidth=125000
      modulation="LORA"
      spreading_factors=[7, 8, 9, 10]

    [[regions.gateway.channels]]
      frequency=903300000
      bandwidth=125000
      modulation="LORA"
      spreading_factors=[7, 8, 9, 10]

    [[regions.gateway.channels]]
      frequency=903500000
      bandwidth=125000
      modulation="LORA"
      spreading_factors=[7, 8, 9, 10]

    [[regions.gateway.channels]]
      frequency=903700000
      bandwidth=125000
      modulation="LORA"
      spreading_factors=[7, 8, 9, 10]

    [[regions.gateway.channels]]
      frequency=903000000
      bandwidth=500000
      modulation="LORA"
      spreading_factors=[8]


    # Add the remaining channel frequencies for 8 - 15 + 65 below


  [regions.network]
    rx2_dr=8
    rx2_frequency=923300000
    min_dr=0
    max_dr=3
    enabled_uplink_channels=[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 64, 65]

    [regions.network.class_b]
      ping_slot_dr=8
      ping_slot_frequency=0

Save this as region_us915_0_1.toml and add us915_0_1 to the enabled regions in your chirpstack.toml file. Make sure your gateway then forwards to the us915_0_1/gateway/.... MQTT topic.

@brocaar If I set the gateway server to recognize 0-16, but the physical gateway only allows for 8 channels will there be an issue on the gateway server side?

My goal here was to have different gateways on different sub bands when in close proximity to each other.

So I want the ability to choose the US sub_band based on the gateway setup.

The [[regions.gateway.channels]] configuration is only used if you are using the Concentratord on your gateways. In this case ChirpStack will send this configuration to your gateway(s) to configure the correct channels. In any other case, ChirpStack will not control the channel config of your gateways, in which case you could have a mix of configurations in your deployment (e.g. gateways with channels 0-7 and 8-15).

@brocaar - thanks for the clarification. When I was adding a physical gateway to chirpstackv4 I only saw the channel that I configured; US915_0. So this is why I was confused and thought I needed to modify the config to have all the channels and then modify the physical gateway. It sounds like that is not the case.

@brocaar - To understand more clearly, the configuration setup on the server for the gateway is used to automatically configure gateways that have the chirpstack gateway software installed. I believe this is what you are saying.

This would make sense in that this is the case. This does not impact any of the gateway subbands I set up as they would not require server side configuration. Such as adding 3 new gateways that are all on different sub bands.

I am asking detailed questions as I am having an issue with a Laird RG191. If is failing to reconnect to the server. It is resolved once I reboot the physical gateway. Laird has asked me to try and use the Basic Station Forwarder and not use the UDP packet forwarder. Do you have any details on how to properly set this up on the server side? I could not seem to find detailed information or up to date information regarding v4.

To clarify, concentratord is Chirpstack’s gateway software and this is specific to Chirpstack. Most gateways would support the Semtech UDP Packet Forwarder, which is not specific to any LoRa Network Server. If you are not using concentratord, do not configure the channels within that section of Chirpstack’s configuration file.

Have you seen this example configuration file for the BasicStation mode of the Chirpstack Gateway Bridge?

In BasicStation mode, the Chirpstack gateway bridge will configure the gateway with the appropriate channels. The channels are specified within the Chirpstack gateway bridge’s configuration file.

@sp193 It looks like I will need to completely rewrite the chirpstack-gateway-bridge.toml. The one that is setup in v4 is just a udp-packet forwarder.

I think I can just drop in the new backend piece and set it. I will make sure to use the US915_0 for testing.

Otherwise I was going to replace the chirpstack-gateway-bridge.toml with the entire configuration file found here: chirpstack-gateway-bridge.toml

Ill take any advice at this point to get a stable gateway.

There is a big change in configuration file content, but it is caused by the gateway concentrator configuration being moved into the Chirpstack Gateway Bridge component, inside the LNS.

Unlike the classic UDP Packet Forwarder, the channels etc, are configured from the LNS.

The UDP Packet Forwarder has been around for a long time and the major gateway brands have their own flavours. As with any software component developed by/provided by the vendor, there could be issues and the vendor should be able to support you.

@sp193 that is what I have gathered from the recent conversations and your comments.

Do you know where there are instructions on setting up the Basic Station Forwarder for V4? Was my previous comment correct in terms of procedure to add the basic station to the chirpstack-gateway-bridge.toml?

Regardless of this specific vendor, I am setting up a few other gateways from different vendors as part of hardware testing and reliability.

I think, using one of the examples as a basis of your new configuration file is easier. If you used the packet forwarder, the only thing in common is just the credentials, address and topics for MQTT. You seem to have roughly the right idea, to try this change out with the sub-band that you are presently using (to minimize unnecessary changes at this point).

Sorry, I do not know where this is documented, if anywhere at all. Being a software engineer, sometimes things just click for me, by seeing examples.