How do you connect your Java Producer to a preconfigured Kafka in Red Panda?

Question

I'm learning Kafka via Conduktor. I ran this command on their get-started page:

curl -L https://releases.conduktor.io/console -o docker-compose.yml && docker compose up -d --wait && echo "Conduktor started on http://localhost:8080"

Now when I visit the console and view the connection, I see it has a bootstrap server of redpanda-1:9021

What confuses me is I cannot seem to access this in my Java Producer/Consumer application. It just simply cannot find it. I assume it is because it is in a container?

EDIT: Already voted to close. Yep, I asked this question with minimal understanding of Kafka, and was just hoping to be able to use the "preconfigured kafka" inside Conduktor for immediate use in a Java App. All good now. Thank you all for your answers.

Answer 1

Unclear what you mean "preconfigured". The file in the link doesn't run any broker, only Postgres database and Conduktor console container.

If you want to run RedPanda, you need to edit that compose file rather than immediately up it.

If RedPanda broker is running in an existing container, then you still need to modify the Compose file to add networks so that redpanda-1 is a known DNS address.

cannot seem to access this in my Java Producer/Consumer application

Related - Connect to Kafka running in Docker

Answer 2

Your question, "..preconfigured Kafka in Red Panda..", implies that you haven't understood the relationship between Kafka, Redpanda, and Conduktor.

Redpanda is a streaming data platform similar to Kafka, sharing the same read/write APIs, and has an entirely different architecture. Therefore, Redpanda is a drop-in replacement for Apache Kafka workloads if you are looking for more performance and cost-efficiency. You can connect your existing client applications to Redpanda as if they are connecting to Kafka because they share the same API interface.

Conduktor is a Developer Experience platform for Kafka, helping developers to debug and administer their Kafka clusters. I think the Conduktor Console has an embedded Redpanda container to make things simpler for beginners.

To solve your connectivity issue, make sure you edit the docker-compose file and expose port 9201 where the Redpanda container is going to bind.

If you want to test Redpanda in isolation, you can try out their quickstart guide on Docker. https://docs.redpanda.com/22.3/get-started/quick-start/