title: Broker may not be available in connecting kafka connector with kafka broker in docker compose
body: <p>I am using docker container to build zookeeper, kafka and connect.</p>
  <pre><code>version: '2.1'
  services:
  
  
    zookeeper:
      image: debezium/zookeeper
      ports:
       - 2181:2181
       - 2888:2888
       - 3888:3888
    kafka:
      image: wurstmeister/kafka
      container_name: kafka-multibinder-1
      ports:
        - &quot;9092:9092&quot;
        - &quot;9094:9094&quot;
  
      environment:
        - KAFKA_ADVERTISED_HOST_NAME=127.0.0.1
        - KAFKA_ADVERTISED_PORT=9092
        - KAFKA_ZOOKEEPER_CONNECT=zookeeper:2181
  
        - KAFKA_ADVERTISED_LISTENERS=INSIDE://:9094,OUTSIDE://localhost:9092
        - KAFKA_LISTENERS=INSIDE://:9094,OUTSIDE://:9092
        - KAFKA_LISTENER_SECURITY_PROTOCOL_MAP=INSIDE:PLAINTEXT,OUTSIDE:PLAINTEXT
        - KAFKA_INTER_BROKER_LISTENER_NAME=INSIDE
  
      depends_on:
        - zookeeper
  
    kafka-connect:
      image: debezium/connect
      hostname: kafka-connect
      ports:
       - 8083:8083
      depends_on:
       - kafka
      environment:
       BOOTSTRAP_SERVERS: kafka:9092
       GROUP_ID: 1
       CONFIG_STORAGE_TOPIC: my_connect_configs
       OFFSET_STORAGE_TOPIC: my_connect_offsets
  </code></pre>
  <p>however the logs warms me that 'could not be established. Broker may not be available'</p>
  <pre><code>kafka-connect_1  | 2020-10-18 04:11:44,671 INFO   ||  Kafka version: 2.5.0   [org.apache.kafka.common.utils.AppInfoParser]
  kafka-connect_1  | 2020-10-18 04:11:44,672 INFO   ||  Kafka commitId: 66563e712b0b9f84   [org.apache.kafka.common.utils.AppInfoParser]
  kafka-connect_1  | 2020-10-18 04:11:44,674 INFO   ||  Kafka startTimeMs: 1602994304669   [org.apache.kafka.common.utils.AppInfoParser]
  kafka-connect_1  | 2020-10-18 04:11:44,806 WARN   ||  [AdminClient clientId=adminclient-1] Connection to node -1 (/127.0.0.1:9092) could not be established. Broker may not be available.   [org.apache.kafka.clients.NetworkClient]
  kafka-connect_1  | 2020-10-18 04:11:44,918 WARN   ||  [AdminClient clientId=adminclient-1] Connection to node -1 (/127.0.0.1:9092) could not be established. Broker may not be available.   [org.apache.kafka.clients.NetworkClient]
  kafka-connect_1  | 2020-10-18 04:11:45,024 WARN   ||  [AdminClient clientId=adminclient-1] Connection to node -1 (/127.0.0.1:9092) could not be established. Broker may not be available.   [org.apache.kafka.clients.NetworkClient]
  kafka-connect_1  | 2020-10-18 04:12:44,713 INFO   ||  [AdminClient clientId=adminclient-1] Metadata update failed   [org.apache.kafka.clients.admin.internals.AdminMetadataManager]
  kafka-connect_1  | org.apache.kafka.common.errors.TimeoutException: Call(callName=fetchMetadata, deadlineMs=1602994364719) timed out at 9223372036854775807 after 1 attempt(s)
  kafka-connect_1  | Caused by: org.apache.kafka.common.errors.TimeoutException: The AdminClient thread has exited.
  kafka-connect_1  | 2020-10-18 04:12:44,722 ERROR  ||  Stopping due to error   [org.apache.kafka.connect.cli.ConnectDistributed]
  kafka-connect_1  | org.apache.kafka.connect.errors.ConnectException: Failed to connect to and describe Kafka cluster. Check worker's broker connection and security properties.
  kafka-connect_1  |  at org.apache.kafka.connect.util.ConnectUtils.lookupKafkaClusterId(ConnectUtils.java:64)
  kafka-connect_1  |  at org.apache.kafka.connect.util.ConnectUtils.lookupKafkaClusterId(ConnectUtils.java:45)
  kafka-connect_1  |  at org.apache.kafka.connect.cli.ConnectDistributed.startConnect(ConnectDistributed.java:95)
  kafka-connect_1  |  at org.apache.kafka.connect.cli.ConnectDistributed.main(ConnectDistributed.java:78)
  kafka-connect_1  | Caused by: java.util.concurrent.ExecutionException: org.apache.kafka.common.errors.TimeoutException: Call(callName=listNodes, deadlineMs=1602994364707) timed out at 1602994364708 after 1 attempt(s)
  kafka-connect_1  |  at org.apache.kafka.common.internals.KafkaFutureImpl.wrapAndThrow(KafkaFutureImpl.java:45)
  kafka-connect_1  |  at org.apache.kafka.common.internals.KafkaFutureImpl.access$000(KafkaFutureImpl.java:32)
  kafka-connect_1  |  at org.apache.kafka.common.internals.KafkaFutureImpl$SingleWaiter.await(KafkaFutureImpl.java:89)
  kafka-connect_1  |  at org.apache.kafka.common.internals.KafkaFutureImpl.get(KafkaFutureImpl.java:260)
  kafka-connect_1  |  at org.apache.kafka.connect.util.ConnectUtils.lookupKafkaClusterId(ConnectUtils.java:58)
  kafka-connect_1  |  ... 3 more
  kafka-connect_1  | Caused by: org.apache.kafka.common.errors.TimeoutException: Call(callName=listNodes, deadlineMs=1602994364707) timed out at 1602994364708 after 1 attempt(s)
  kafka-connect_1  | Caused by: org.apache.kafka.common.errors.TimeoutException: Timed out waiting for a node assignment.
  </code></pre>