Kafka proxy inside eks cluster exposed to localhost not working

[I-Abdelhamid]

Hello,
I have eks cluster that have access to msk. I deployed the following according to the documentation

---
apiVersion: apps/v1
kind: StatefulSet
metadata:
   name: kafka-proxy
spec:
  selector:
    matchLabels:
      app: kafka-proxy
  replicas: 1
  serviceName: kafka-proxy
  template:
    metadata:
      labels:
        app: kafka-proxy
    spec:
      containers:
        - name: kafka-proxy
          image: grepplabs/kafka-proxy:latest
          args:
            - 'server'
            - '--log-format=json'
            - '--bootstrap-server-mapping=************,127.0.0.1:32400'
            - '--bootstrap-server-mapping=************,127.0.0.1:32401'
            - '--bootstrap-server-mapping=************,127.0.0.1:32402'
            - '--proxy-request-buffer-size=32768'
            - '--proxy-response-buffer-size=32768'
            - '--proxy-listener-read-buffer-size=32768'
            - '--proxy-listener-write-buffer-size=131072'
            - '--kafka-connection-read-buffer-size=131072'
            - '--kafka-connection-write-buffer-size=32768'
          ports:
          - name: metrics
            containerPort: 9080
          - name: kafka-0
            containerPort: 32400
          - name: kafka-1
            containerPort: 32401
          - name: kafka-2
            containerPort: 32402
          livenessProbe:
            httpGet:
              path: /health
              port: 9080
            initialDelaySeconds: 5
            periodSeconds: 3
          readinessProbe:
            httpGet:
              path: /health
              port: 9080
            initialDelaySeconds: 5
            periodSeconds: 10
            timeoutSeconds: 5
            successThreshold: 2
            failureThreshold: 5
          resources:
            requests:
              memory: 128Mi
              cpu: 1000m
      restartPolicy: Always

now when I port forward according to the documentation to my localhost machine
kubectl port-forward kafka-proxy-0 32400:32400 32401:32401 32402:32402
then try kcat -b localhost:32400,localhost:32401,localhost:32402 -t topic1 it gives me the timing-out and the following

%3|1675126714.187|FAIL|rdkafka#consumer-1| [thrd:0.0.0.0:44357/1]: 0.0.0.0:44357/1: Connect to ipv4#0.0.0.0:44357 failed: Connection refused (after 0ms in state CONNECT)
%3|1675126714.187|FAIL|rdkafka#consumer-1| [thrd:0.0.0.0:35303/2]: 0.0.0.0:35303/2: Connect to ipv4#0.0.0.0:35303 failed: Connection refused (after 0ms in state CONNECT)
% ERROR: Local: Broker transport failure: 0.0.0.0:44357/1: Connect to ipv4#0.0.0.0:44357 failed: Connection refused (after 0ms in state CONNECT)
% ERROR: Local: Broker transport failure: 0.0.0.0:35303/2: Connect to ipv4#0.0.0.0:35303 failed: Connection refused (after 0ms in state CONNECT)
%3|1675126714.341|FAIL|rdkafka#consumer-1| [thrd:0.0.0.0:35303/2]: 0.0.0.0:35303/2: Connect to ipv4#0.0.0.0:35303 failed: Connection refused (after 0ms in state CONNECT, 1 identical error(s) suppressed)
% ERROR: Local: Broker transport failure: 0.0.0.0:35303/2: Connect to ipv4#0.0.0.0:35303 failed: Connection refused (after 0ms in state CONNECT, 1 identical error(s) suppressed)
%3|1675126714.403|FAIL|rdkafka#consumer-1| [thrd:0.0.0.0:44357/1]: 0.0.0.0:44357/1: Connect to ipv4#0.0.0.0:44357 failed: Connection refused (after 1ms in state CONNECT, 1 identical error(s) suppressed)
% ERROR: Local: Broker transport failure: 0.0.0.0:44357/1: Connect to ipv4#0.0.0.0:44357 failed: Connection refused (after 1ms in state CONNECT, 1 identical error(s) suppressed)

Notes:
No auth needed from eks pod side
can't expose the proxy through elb, I can only use port forward for local use

[chalimbu]

Hi had the same problem and it's likely becuase of the 127.0.0.1 even though it works locally in Kubernetes is not going to bind to all the ips.
tyr changing it to 0.0.0.0