Hadoop Fail to Connect to ResourceManager <p>I am just testing out hadoop by running a wordcount example, but this error came up:</p> <pre><code>14/07/30 12:03:02 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable 14/07/30 12:03:03 INFO client.RMProxy: Connecting to ResourceManager at /127.0.0.1:8032 14/07/30 12:03:04 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:8032. Already tried 0 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS) 14/07/30 12:03:05 INFO ipc.Client: Retrying connect to server: localhost/127.0.0.1:8032. Already tried 1 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS) </code></pre> <p>Some people on the internet have suggested it's because of the yarn-site.xml file. Mine is:</p> <pre><code> &lt;property&gt; &lt;name&gt;yarn.nodemanager.aux-services&lt;/name&gt; &lt;value&gt;mapreduce_shuffle&lt;/value&gt; &lt;/property&gt; &lt;property&gt; &lt;name&gt;yarn.nodemanager.aux-services.mapreduce.shuffle.class&lt;/name&gt; &lt;value&gt;org.apache.hadoop.mapred.ShuffleHandler&lt;/value&gt; &lt;/property&gt; &lt;property&gt; &lt;name&gt;yarn.scheduler.minimum-allocation-mb&lt;/name&gt; &lt;value&gt;128&lt;/value&gt; &lt;description&gt;Minimum limit of memory to allocate to each container request at the Resource Manager.&lt;/description&gt; &lt;/property&gt; &lt;property&gt; &lt;name&gt;yarn.scheduler.maximum-allocation-mb&lt;/name&gt; &lt;value&gt;1024&lt;/value&gt; &lt;description&gt;Maximum limit of memory to allocate to each container request at the Resource Manager.&lt;/description&gt; &lt;/property&gt; &lt;property&gt; &lt;name&gt;yarn.scheduler.minimum-allocation-vcores&lt;/name&gt; &lt;value&gt;1&lt;/value&gt; &lt;description&gt;The minimum allocation for every container request at the RM, in terms of virtual CPU cores. Requests lower than this won't take effect, and the specified value will get allocated the minimum.&lt;/description&gt; &lt;/property&gt; &lt;property&gt; &lt;name&gt;yarn.scheduler.maximum-allocation-vcores&lt;/name&gt; &lt;value&gt;2&lt;/value&gt; &lt;description&gt;The maximum allocation for every container request at the RM, in terms of virtual CPU cores. Requests higher than this won't take effect, and will get capped to this value.&lt;/description&gt; &lt;/property&gt; &lt;property&gt; &lt;name&gt;yarn.nodemanager.resource.memory-mb&lt;/name&gt; &lt;value&gt;2048&lt;/value&gt; &lt;description&gt;Physical memory, in MB, to be made available to running containers&lt;/description&gt; &lt;/property&gt; &lt;property&gt; &lt;name&gt;yarn.nodemanager.resource.cpu-vcores&lt;/name&gt; &lt;value&gt;2&lt;/value&gt; &lt;description&gt;Number of CPU cores that can be allocated for containers.&lt;/description&gt; &lt;/property&gt; &lt;property&gt; &lt;name&gt;yarn.nodemanager.aux-services&lt;/name&gt; &lt;value&gt;mapreduce_shuffle&lt;/value&gt; &lt;/property&gt; </code></pre> <p>I ran programs last week and it was working fine, so I really can't figure out what is going on. Help is appreciated.</p>