title: Ruby Kafka Uncaught exception: Failed to find group coordinator
body: <p>I use Apache Kafka as Docker container <a href="https://hub.docker.com/r/wurstmeister/kafka/" rel="nofollow noreferrer">https://hub.docker.com/r/wurstmeister/kafka/</a></p>
  
  <p>I'm able to successfully connect to Kafka from my Java application with Spring Kafka.</p>
  
  <p>But when I try to connect to Kafka from the Ruby application via Ruby Kafka I receive the following error:</p>
  
  <pre><code>Uncaught exception: Failed to find group coordinator
  </code></pre>
  
  <p>The only difference between the Java and Ruby applications - is that Ruby application is located on another machine in my local network but I can see the Kafka machine from Ruby machine and all of the ports there. </p>
  
  <p>How to find the issue and solve it?</p>
  
  <p><strong>UPDATED</strong></p>
  
  <pre><code>I, [2018-06-25T10:06:49.513848 #62261]  INFO -- : New topics added to target list: post.sent
  I, [2018-06-25T10:06:49.514036 #62261]  INFO -- : Fetching cluster metadata from kafka://10.0.0.102:9093
  D, [2018-06-25T10:06:49.514262 #62261] DEBUG -- : Opening connection to 10.0.0.102:9093 with client id test...
  D, [2018-06-25T10:06:49.518350 #62261] DEBUG -- : Sending topic_metadata API request 1 to 10.0.0.102:9093
  D, [2018-06-25T10:06:49.519336 #62261] DEBUG -- : Waiting for response 1 from 10.0.0.102:9093
  D, [2018-06-25T10:06:49.530220 #62261] DEBUG -- : Received response 1 from 10.0.0.102:9093
  I, [2018-06-25T10:06:49.530351 #62261]  INFO -- : Discovered cluster metadata; nodes: 10.0.75.1:9093 (node_id=1001)
  D, [2018-06-25T10:06:49.530439 #62261] DEBUG -- : Closing socket to 10.0.0.102:9093
  I, [2018-06-25T10:06:49.530682 #62261]  INFO -- : Joining group `my_group`
  D, [2018-06-25T10:06:49.530812 #62261] DEBUG -- : Getting group coordinator for `my_group`
  D, [2018-06-25T10:06:49.531019 #62261] DEBUG -- : Opening connection to 10.0.75.1:9093 with client id test...
  D, [2018-06-25T10:06:49.616368 #62261] DEBUG -- : Handling fetcher command: subscribe
  I, [2018-06-25T10:06:49.616797 #62261]  INFO -- : Will fetch at most 1048576 bytes at a time per partition from post.sent
  D, [2018-06-25T10:06:49.617262 #62261] DEBUG -- : Handling fetcher command: configure
  D, [2018-06-25T10:06:49.617462 #62261] DEBUG -- : Handling fetcher command: start
  D, [2018-06-25T10:06:49.617599 #62261] DEBUG -- : Fetching batches
  I, [2018-06-25T10:06:49.618108 #62261]  INFO -- : Fetching cluster metadata from kafka://10.0.0.102:9093
  D, [2018-06-25T10:06:49.619053 #62261] DEBUG -- : Opening connection to 10.0.0.102:9093 with client id test...
  D, [2018-06-25T10:06:49.624053 #62261] DEBUG -- : Sending topic_metadata API request 1 to 10.0.0.102:9093
  D, [2018-06-25T10:06:49.625459 #62261] DEBUG -- : Waiting for response 1 from 10.0.0.102:9093
  D, [2018-06-25T10:06:49.635283 #62261] DEBUG -- : Received response 1 from 10.0.0.102:9093
  I, [2018-06-25T10:06:49.635468 #62261]  INFO -- : Discovered cluster metadata; nodes: 10.0.75.1:9093 (node_id=1001)
  D, [2018-06-25T10:06:49.635596 #62261] DEBUG -- : Closing socket to 10.0.0.102:9093
  I, [2018-06-25T10:06:49.635853 #62261]  INFO -- : There are no partitions to fetch from, sleeping for 1s
  D, [2018-06-25T10:06:50.637187 #62261] DEBUG -- : Fetching batches
  I, [2018-06-25T10:06:50.637804 #62261]  INFO -- : There are no partitions to fetch from, sleeping for 1s
  D, [2018-06-25T10:06:51.642172 #62261] DEBUG -- : Fetching batches
  I, [2018-06-25T10:06:51.642471 #62261]  INFO -- : There are no partitions to fetch from, sleeping for 1s
  D, [2018-06-25T10:06:52.645354 #62261] DEBUG -- : Fetching batches
  I, [2018-06-25T10:06:52.645640 #62261]  INFO -- : There are no partitions to fetch from, sleeping for 1s
  D, [2018-06-25T10:06:53.647833 #62261] DEBUG -- : Fetching batches
  I, [2018-06-25T10:06:53.648259 #62261]  INFO -- : There are no partitions to fetch from, sleeping for 1s
  D, [2018-06-25T10:06:54.650357 #62261] DEBUG -- : Fetching batches
  I, [2018-06-25T10:06:54.650647 #62261]  INFO -- : There are no partitions to fetch from, sleeping for 1s
  D, [2018-06-25T10:06:55.652582 #62261] DEBUG -- : Fetching batches
  I, [2018-06-25T10:06:55.653477 #62261]  INFO -- : There are no partitions to fetch from, sleeping for 1s
  D, [2018-06-25T10:06:56.657937 #62261] DEBUG -- : Fetching batches
  I, [2018-06-25T10:06:56.659627 #62261]  INFO -- : There are no partitions to fetch from, sleeping for 1s
  D, [2018-06-25T10:06:57.664130 #62261] DEBUG -- : Fetching batches
  I, [2018-06-25T10:06:57.664861 #62261]  INFO -- : There are no partitions to fetch from, sleeping for 1s
  D, [2018-06-25T10:06:58.666290 #62261] DEBUG -- : Fetching batches
  I, [2018-06-25T10:06:58.666620 #62261]  INFO -- : There are no partitions to fetch from, sleeping for 1s
  E, [2018-06-25T10:06:59.534809 #62261] ERROR -- : Timed out while trying to connect to 10.0.75.1:9093: Operation timed out
  D, [2018-06-25T10:06:59.535083 #62261] DEBUG -- : Closing socket to 10.0.75.1:9093
  E, [2018-06-25T10:06:59.535342 #62261] ERROR -- : Failed to get group coordinator info from 10.0.75.1:9093 (node_id=1001): Operation timed out
  I, [2018-06-25T10:06:59.535567 #62261]  INFO -- : Leaving group `my_group`
  D, [2018-06-25T10:06:59.535709 #62261] DEBUG -- : Getting group coordinator for `my_group`
  D, [2018-06-25T10:06:59.535875 #62261] DEBUG -- : Opening connection to 10.0.75.1:9093 with client id test...
  D, [2018-06-25T10:06:59.666983 #62261] DEBUG -- : Handling fetcher command: stop
  E, [2018-06-25T10:07:09.540409 #62261] ERROR -- : Timed out while trying to connect to 10.0.75.1:9093: Operation timed out
  D, [2018-06-25T10:07:09.540833 #62261] DEBUG -- : Closing socket to 10.0.75.1:9093
  E, [2018-06-25T10:07:09.541172 #62261] ERROR -- : Failed to get group coordinator info from 10.0.75.1:9093 (node_id=1001): Operation timed out
  Exiting
  Uncaught exception: Failed to find group coordinator
  </code></pre>