title: No appenders could be found for logger (org.apache.kafka.clients.consumer.ConsumerConfig)
body: <p>I am trying to connect Apache Kafka to Apache Flink by creating a Kafka Consumer in Scala. This is my Consumer code:</p>
  
  <pre><code>val properties = new Properties()
  properties.setProperty("bootstrap.servers", "localhost:9092")
  properties.setProperty("zookeeper.connect", "localhost:2181")
  properties.setProperty("group.id", "test")
  
  val env = StreamExecutionEnvironment.getExecutionEnvironment
  val stream = env
              .addSource(new FlinkKafkaConsumer09[String]("test", new  SimpleStringSchema(), properties))
              .print
  env.enableCheckpointing(5000)
  </code></pre>
  
  <p>When I run this program I get some warnings from log4j and the program terminates, no output is shown. My Kafka Producer is up and running.</p>
  
  <pre><code>log4j:WARN No appenders could be found for logger (org.apache.kafka.clients.consumer.ConsumerConfig).
  log4j:WARN Please initialize the log4j system properly.
  log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
  </code></pre>