title: How to create Kafka user and consumer group for ACLs in a running cluster?
body: <p>I'm using Kafka 2.1 in SASL_PLAINTEXT mode and for controlling ACLs on topics I need to create users and groups. So how can I create a user in running cluster?</p>
  
  <p>I know that I can use <code>kafka-consumer-groups.sh</code> to create and list groups. but when I try to list groups it throws <code>Failed to find brokers to send ListGroups</code> exception.</p>