title: Datastax driver connection exception DSE 5.0 , CASSANDRA 3.0.7 ,spark
body: <p>I am trying to understand the warning, every time i am seeing the below exception when i run my spark job .I am seeing this in 2 nodes of my 3 node cluster.But as i said its just warn , job succeeds how ever.</p>
  
  <pre><code>com.datastax.driver.core.exceptions.ConnectionException: [x.x.x.x/x.x.x.x:9042] Pool was closed during initialization
  </code></pre>
  
  <p>CASSANDRA LOG </p>
  
  <blockquote>
    <p>INFO  [SharedPool-Worker-1] 2017-07-17 22:25:48,716  Message.java:605
    - Unexpected exception during request; channel = [id: 0xf0ee1096, /x.x.x.x:54863 => /x.x.x.x:9042]
    io.netty.channel.unix.Errors$NativeIoException: readAddress() failed:
    Connection timed out
            at io.netty.channel.unix.Errors.newIOException(Errors.java:105)
    ~[netty-all-4.0.34.Final.jar:4.0.34.Final]
            at io.netty.channel.unix.Errors.ioResult(Errors.java:121) ~[netty-all-4.0.34.Final.jar:4.0.34.Final]
            at io.netty.channel.unix.FileDescriptor.readAddress(FileDescriptor.java:134)
    ~[netty-all-4.0.34.Final.jar:4.0.34.Final]
            at io.netty.channel.epoll.AbstractEpollChannel.doReadBytes(AbstractEpollChannel.java:239)
    ~[netty-all-4.0.34.Final.jar:4.0.34.Final]
            at io.netty.channel.epoll.AbstractEpollStreamChannel$EpollStreamUnsafe.epollInReady(AbstractEpollStreamChannel.java:822)
    ~[netty-all-4.0.34.Final.jar:4.0.34.Final]
            at io.netty.channel.epoll.EpollEventLoop.processReady(EpollEventLoop.java:348)
    ~[netty-all-4.0.34.Final.jar:4.0.34.Final]
            at io.netty.channel.epoll.EpollEventLoop.run(EpollEventLoop.java:264)
    ~[netty-all-4.0.34.Final.jar:4.0.34.Final]
            at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:112)
    ~[netty-all-4.0.34.Final.jar:4.0.34.Final]
            at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:137)
    ~[netty-all-4.0.34.Final.jar:4.0.34.Final]
            at java.lang.Thread.run(Thread.java:745) [na:1.8.0_121]</p>
  </blockquote>