running Kafka on WSL and make producer on windows

Question

I'm running Kafka on WSL. I'm trying to make simple producer like this (I'm using intellj)

import org.apache.kafka.clients.producer.KafkaProducer;
import org.apache.kafka.clients.producer.ProducerConfig;
import org.apache.kafka.clients.producer.ProducerRecord;
import org.apache.kafka.common.serialization.StringSerializer;

import java.util.Properties;

public class ProducerDemo {

    public static void main(String[] args) {

        String bootstrapServers = "127.0.0.1:9092";

        //create Producer properties
        Properties properties = new Properties();
        properties.setProperty(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG,bootstrapServers);
        properties.setProperty(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class.getName());
        properties.setProperty(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG,StringSerializer.class.getName());

        //create the producer
        KafkaProducer producer = new KafkaProducer(properties);

        //create a producer record
        ProducerRecord record =
                new ProducerRecord("first_topic","hallo world");

        //send data
        producer.send(record);

        //flush + close
        producer.flush();
        producer.close();
    }

}

but there's a problem, when I try to run the code it shows this error

[kafka-producer-network-thread | producer-1] WARN org.apache.kafka.clients.NetworkClient - [Producer clientId=producer-1] Error connecting to node AD17-2.localdomain:9092 (id: 0 rack: null)
java.net.UnknownHostException: No such host is known (AD17-2.localdomain)
    at java.base/java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)
    at java.base/java.net.InetAddress$PlatformNameService.lookupAllHostAddr(InetAddress.java:932)
    at java.base/java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1505)
    at java.base/java.net.InetAddress$NameServiceAddresses.get(InetAddress.java:851)
    at java.base/java.net.InetAddress.getAllByName0(InetAddress.java:1495)
    at java.base/java.net.InetAddress.getAllByName(InetAddress.java:1354)
    at java.base/java.net.InetAddress.getAllByName(InetAddress.java:1288)
    at org.apache.kafka.clients.ClientUtils.resolve(ClientUtils.java:110)
    at org.apache.kafka.clients.ClusterConnectionStates$NodeConnectionState.currentAddress(ClusterConnectionStates.java:403)
    at org.apache.kafka.clients.ClusterConnectionStates$NodeConnectionState.access$200(ClusterConnectionStates.java:363)
    at org.apache.kafka.clients.ClusterConnectionStates.currentAddress(ClusterConnectionStates.java:151)
    at org.apache.kafka.clients.NetworkClient.initiateConnect(NetworkClient.java:955)
    at org.apache.kafka.clients.NetworkClient.ready(NetworkClient.java:293)
    at org.apache.kafka.clients.producer.internals.Sender.sendProducerData(Sender.java:350)
    at org.apache.kafka.clients.producer.internals.Sender.runOnce(Sender.java:323)
    at org.apache.kafka.clients.producer.internals.Sender.run(Sender.java:239)
    at java.base/java.lang.Thread.run(Thread.java:832)

Process finished with exit code -1

i even checked the port on my Windows

TCP    0.0.0.0:9092           0.0.0.0:0              LISTENING

my question is, is it impossible to make producer on windows and while running kafka on WSL ?

user_350613 · Answer

Your Kafka broker is using the local hostname (AD17-2.localdomain) in its advertised listener. When you client connects to it initially on 127.0.0.1:9092 the broker returns this address for it to connect to for producing messages. Your producer fails to resolve this address, and fails.

To fix it, in the broker's server.properties set

advertised.listeners=PLAINTEXT://127.0.0.1:9092
listener.security.protocol.map=PLAINTEXT:PLAINTEXT
listeners=PLAINTEXT://0.0.0.0:9092

More info: https://rmoff.net/2018/08/02/kafka-listeners-explained/

user_4210386 · Answer

It works for me with this solution: Whit the command: "ip addr | grep eth0" on Ubuntu terminal I can get external interface IP, I set this IP on advertised.listener and with the command:

netsh interface portproxy add v4tov4 listenport=9092 listenaddress=0.0.0.0 connectport=9092 connectaddress=XXX.XX.XX.XX

on Windows cmd I can forward ports. With the command "netstat -ab" I can see on Windows cmd the IP and Port TCP 0.0.0.0:9092. It works correctly! Running Kafka Confluent Platform on WSL 2 (Ubuntu Distribution) and Spring application on Windows (Broker may not be available)

running Kafka on WSL and make producer on windows

2 Answers