TimeoutException: Timeout expired while fetching t

问题:

I have been trying to deploy Kafka with schema registry locally using Kubernetes. However, the logs of the schema registry pod show this error message:

ERROR Server died unexpectedly:  (io.confluent.kafka.schemaregistry.rest.SchemaRegistryMain:51)
org.apache.kafka.common.errors.TimeoutException: Timeout expired while fetching topic metadata

What could be the reason of this behavior? ' In order to run Kubernetes locally, I user Minikube version v0.32.0 with Kubernetes version v1.13.0

My Kafka configuration:

apiVersion: v1
kind: Service
metadata:
  name: kafka-1
spec:
  ports:
    - name: client
      port: 9092
  selector:
    app: kafka
    server-id: "1"
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: kafka-1
spec:
  selector:
    matchLabels:
      app: kafka
      server-id: "1"
  replicas: 1
  template:
    metadata:
      labels:
        app: kafka
        server-id: "1"
    spec:
      volumes:
        - name: kafka-data
          emptyDir: {}
      containers:
        - name: server
          image: confluent/kafka:0.10.0.0-cp1
          env:
            - name: KAFKA_ZOOKEEPER_CONNECT
              value: zookeeper-1:2181
            - name: KAFKA_ADVERTISED_HOST_NAME
              value: kafka-1
            - name: KAFKA_BROKER_ID
              value: "1"
          ports:
            - containerPort: 9092
          volumeMounts:
            - mountPath: /var/lib/kafka
              name: kafka-data
---
apiVersion: v1
kind: Service
metadata:
  name: schema
spec:
  ports:
    - name: client
      port: 8081
  selector:
    app: kafka-schema-registry
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: kafka-schema-registry
spec:
  replicas: 1
  selector:
    matchLabels:
      app: kafka-schema-registry
  template:
    metadata:
      labels:
        app: kafka-schema-registry
    spec:
      containers:
        - name: kafka-schema-registry
          image: confluent/schema-registry:3.0.0
          env:
            - name: SR_KAFKASTORE_CONNECTION_URL
              value: zookeeper-1:2181
            - name: SR_KAFKASTORE_TOPIC
              value: "_schema_registry"
            - name: SR_LISTENERS
              value: "http://0.0.0.0:8081"
          ports:
            - containerPort: 8081

Zookeeper configuraion:

apiVersion: v1
kind: Service
metadata:
  name: zookeeper
spec:
  ports:
    - name: client
      port: 2181
  selector:
    app: zookeeper
---
apiVersion: v1
kind: Service
metadata:
  name: zookeeper-1
spec:
  ports:
    - name: client
      port: 2181
    - name: followers
      port: 2888
    - name: election
      port: 3888
  selector:
    app: zookeeper
    server-id: "1"
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: zookeeper-1
spec:
  selector:
    matchLabels:
      app: zookeeper
      server-id: "1"
  replicas: 1
  template:
    metadata:
      labels:
        app: zookeeper
        server-id: "1"
    spec:
      volumes:
        - name: data
          emptyDir: {}
        - name: wal
          emptyDir:
            medium: Memory
      containers:
        - name: server
          image: elevy/zookeeper:v3.4.7
          env:
            - name: MYID
              value: "1"
            - name: SERVERS
              value: "zookeeper-1"
            - name: JVMFLAGS
              value: "-Xmx2G"
          ports:
            - containerPort: 2181
            - containerPort: 2888
            - containerPort: 3888
          volumeMounts:
            - mountPath: /zookeeper/data
              name: data
            - mountPath: /zookeeper/wal
              name: wal

回答1:

org.apache.kafka.common.errors.TimeoutException: Timeout expired while fetching topic metadata

can happen when trying to connect to a broker expecting SSL connections and the client config did not specify;

security.protocol=SSL