Kafka Network Flow

2025-12-172025-12-17

Kafka Kraft

flowchart TD
    Application[Producer/Consumer App]
    KafkaBroker[Kafka Broker]
    Controller[KRaft Controller]

    subgraph App_Subnet[APP Subnet]
        Application
    end

    subgraph Infra_Subnet[Infrastructure Subnet - 10.0.1.0/24]
        subgraph Kafka_Cluster[Kafka Kraft]
            KafkaBroker
            Controller
        end
    end

    Application <-->|Produce/Consume Port 9092| KafkaBroker
    KafkaBroker -->|Metadata, Heartbeat, Leader Election| Controller
    Controller -->|Cluster Coordination| KafkaBroker

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Kafka 🐾 Zookeeper

flowchart TD
    Application[Producer/Consumer App]
    Kafka[Kafka Broker]
    Zookeeper[🐾 Zookeeper]
    Controller[Kafka Controller]

    subgraph App_Subnet[APP Subnet]
        Application
    end
   subgraph Infra_Subnet[Infrastructure Subnet - 10.0.1.0/24]
        subgraph Kafka_Cluster[Kafka]
            Kafka_Config[
                server.properties:
                - listener=INTERNAL://0.0.0.0:9093  EXTERNAL://0.0.0.0:9092
                - advertised.listeners=INTERNAL://kafka-int:9093  EXTERNAL://kafka:9092
                - inter.broker.listener.name=INTERNAL
            ]
        end
    end
    subgraph Infra_Subnet[Infra Subnet]
        subgraph Kafka_Cluster[Kafka ZK]
        
        Application <-->|Produce/Consumer Port 9092| Kafka
    Kafka -->|Connect to 2181| Zookeeper
    Controller -->|Leader election via port 3888| Zookeeper
    Kafka -->|Heartbeat & metadata 2181| Zookeeper
    Zookeeper -->|Responds| Kafka
    end
end