title: Unable to start a node manager on master
body: <p>I am setting up a Hadoop YARN cluster and I am using a machine as both a master and a slave. When I start the YARN using the following command, it starts the nodemanager on slaves but not on the master node.</p>
  
  <pre><code>sbin/yarn-daemons.sh start nodemanager
  </code></pre>
  
  <p>I have a master which also is slave and then I have another two slaves within the cluster, the nodemanagers in the slaves are starting properly.</p>
  
  <p>The error I get :</p>
  
  <pre><code>org.apache.hadoop.yarn.exceptions.YarnRuntimeException: java.net.BindException: Problem binding to [0.0.0.0:8040] java.net.BindException: Address already in use; For more details see:  http://wiki.apache.org/hadoop/BindException
  </code></pre>
  
  <p><strong>Output  of some of the Commands .</strong></p>
  
  <pre><code>cat /etc/services | grep 8040
  ampify          8040/tcp                # Ampify Messaging Protocol
  ampify          8040/udp                # Ampify Messaging Protocol
  
  lsof -i tcp:8040
  COMMAND   PID USER   FD   TYPE  DEVICE SIZE/OFF NODE NAME
  java    28021   df  195u  IPv6 3580602      0t0  TCP server1.mydomain.com:ampify (LISTEN
  </code></pre>