title: All host(s) tried for query failed - com.datastax.driver.core.OperationTimedOutException
body: <p>While performing Cassandra operations (Batch execution- insert and update operations on two tables) using spark job I am getting "<strong>All host(s) tried for query failed - com. datastax. driver. core. OperationTimedOutException</strong>" error.</p>
  
  <p><strong>Cluster information:</strong><br>
  Cassandra 2.1.8.621 <strong>|</strong> DSE 4.7.1<br>
  spark-cassandra-connector-java_2.10 version - 1.2.0-rc1 <strong>|</strong>  cassandra-driver-core   version - 2.1.7<br>
  <strong>Spark 1.2.1  | Hadoop 2.7.1</strong> => 3 nodes<br>
  <strong>Cassandra 2.1.8</strong> => 5 nodes<br>
  <strong>Each node having 28 gb memory and 24 cores</strong>  </p>
  
  <p>While searching for it's solution I came across some discussions, which says you should <strong>not use BATCHES</strong>. Though I would like to find the root cause of this error.Also, How and from where to <strong>set/get "SocketOptions. setReadTimeout"</strong>, as this timeout limit must be greater than the Cassandra requests timeout as per standard guideline and to avoid possible errors. </p>
  
  <p>Is the request_timeout_in_ms and the SocketOptions. setReadTimeout same?Can anyone help me with this?</p>