Kafka Brokers <-> Chirpstack Application Server

Hi everyone,

first of all let me apologize in case this ticket is duplicated. I spent some time trying to find a case or documentation that could answer my question. However, I didn´t find anything.

I would like to know how the broker section works for a kafka <-> application server integration . I´ve noted that, although I have more than one broker set, traffic is send (kafka produce packets) only for the first broker configured. See bellow one example:

Three brokers set in the configuration file


Brokers, e.g.: localhost:9092.


I see kafka metadata packets being sent/received between the three brokers and the Chirpstack AS. However the data (kafka produce) is only sent to the first broker configured

So my question is: does it work in an active/standby way? Is the Traffic sent only for the first broker configured and in case it goes down traffic is send to the other? Is there anyway to configure it to send traffic to all brokers configured at the same time?

Thank you all for your help,

I do not have much experience with Kafka, but maybe this answers your questions? (from the TOML config file)

  # Template for keys included in Kafka messages. If empty, no key is included.
  # Kafka uses the key for distributing messages over partitions. You can use
  # this to ensure some subset of messages end up in the same partition, so
  # they can be consumed in-order. And Kafka can use the key for data retention
  # decisions.  A header "event" with the event type is included in each
  # message. There is no need to parse it from the key.
  event_key_template="application.{{ .ApplicationID }}.device.{{ .DevEUI }}.event.{{ .EventType }}"

thank you Brocaar. However, this is the template used for the data being sent. The Chirpstack App Server has sent traffic, but I want to send it to more than one IP address set in brokers section and what I´ve noted it is that it sends traffic just for the first IP configured.



Metadata is sent to all of them, but produce data is sent only for the first one configured.

Hello al,

Does someone have any feedback about it?