title: Exception-"network/Elasticsearch cluster is not accessible or when targeting a WAN/Cloud instance"
body: <p>I have tried running the Spark application for integration of Hbase and ES. I have tried creating the index in ES and storing the data from HBase, but received an issue “ the user is unauthorized or access denied” when connecting to ES server.</p>
  
  <p>I have checked with the Operations team and bounced the ES server, have  attempted running the application and got the attached exception-<strong>Exception in thread "main" org.elasticsearch.hadoop.EsHadoopIllegalArgumentException: Cannot detect ES version - typically this happens if the network/Elasticsearch cluster is not accessible or when targeting a WAN/Cloud instance without the proper setting 'es.nodes.wan.only'</strong>
      at org.elasticsearch.hadoop.rest.InitializationUtils.discoverEsVersion(InitializationUtils.java:327)
      at org.elasticsearch.spark.rdd.EsSpark$.doSaveToEs(EsSpark.scala:103)
      at org.elasticsearch.spark.rdd.EsSpark$.saveToEs(EsSpark.scala:79)
      at org.elasticsearch.spark.rdd.EsSpark$.saveToEs(EsSpark.scala:74)
      at org.elasticsearch.spark.package$SparkRDDFunctions.saveToEs(package.scala:55)</p>
  
  <p>I'm using Elasticsearch 6.1.1 v.Please let me know if anyone faced this issue and cleared the exception</p>