Hi,

I have 3 node Cloudera 5.9 Cluster running on CentOS 6.7.

Recently during any write operation on Hadoop, I am witnessing these errors in Datanode logs. However the write happens but I am concerned why this is happening.

PFB the stack trace.

2017-07-29 10:33:04,109 ERROR org.apache.hadoop.hdfs.server.datanode.DataNode: <datanodename>:50010:DataXceiver error processing WRITE_BLOCK
operation  src: /Y.Y.Y.Y:43298 dst: /X.X.X.X:50010
java.io.IOException: Premature EOF from inputStream
        at org.apache.hadoop.io.IOUtils.readFully(IOUtils.java:201)
        at org.apache.hadoop.hdfs.protocol.datatransfer.PacketReceiver.doReadFully(PacketReceiver.java:213)
        at org.apache.hadoop.hdfs.protocol.datatransfer.PacketReceiver.doRead(PacketReceiver.java:134)
        at org.apache.hadoop.hdfs.protocol.datatransfer.PacketReceiver.receiveNextPacket(PacketReceiver.java:109)
        at org.apache.hadoop.hdfs.server.datanode.BlockReceiver.receivePacket(BlockReceiver.java:500)
        at org.apache.hadoop.hdfs.server.datanode.BlockReceiver.receiveBlock(BlockReceiver.java:896)
        at org.apache.hadoop.hdfs.server.datanode.DataXceiver.writeBlock(DataXceiver.java:802)
        at org.apache.hadoop.hdfs.protocol.datatransfer.Receiver.opWriteBlock(Receiver.java:169)
        at org.apache.hadoop.hdfs.protocol.datatransfer.Receiver.processOp(Receiver.java:106)
        at org.apache.hadoop.hdfs.server.datanode.DataXceiver.run(DataXceiver.java:246)
        at java.lang.Thread.run(Thread.java:745)
2017-07-29 10:36:06,172 ERROR org.apache.hadoop.jmx.JMXJsonServlet: getting attribute DatanodeNetworkCounts of Hadoop:service=DataNode,name=DataNodeInfo threw an except
ion
javax.management.RuntimeMBeanException: java.lang.NullPointerException
        at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrow(DefaultMBeanServerInterceptor.java:839)
        at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrowMaybeMBeanException(DefaultMBeanServerInterceptor.java:852)
        at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:651)
        at com.sun.jmx.mbeanserver.JmxMBeanServer.getAttribute(JmxMBeanServer.java:678)
        at org.apache.hadoop.jmx.JMXJsonServlet.writeAttribute(JMXJsonServlet.java:346)
        at org.apache.hadoop.jmx.JMXJsonServlet.listBeans(JMXJsonServlet.java:324)
        at org.apache.hadoop.jmx.JMXJsonServlet.doGet(JMXJsonServlet.java:217)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
        at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
        at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1221)
        at org.apache.hadoop.http.lib.StaticUserWebFilter$StaticUserFilter.doFilter(StaticUserWebFilter.java:109)
        at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)
        at org.apache.hadoop.http.HttpServer2$QuotingInputFilter.doFilter(HttpServer2.java:1296)
        at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)
        at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)
        at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)
        at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)
        at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)
        at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:399)
        at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
        at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
        at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:767)
        at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
        at org.mortbay.jetty.Server.handle(Server.java:326)
        at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
        at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:928)
        at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549)
        at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)
        at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
        at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)
        at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
Caused by: java.lang.NullPointerException
        at org.apache.hadoop.hdfs.server.datanode.DataNode.getDatanodeNetworkCounts(DataNode.java:1956)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:75)
        at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:606)
        at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:279)
        at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:193)
        at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:175)
        at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:117)
        at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:54)
        at com.sun.jmx.mbeanserver.MBeanIntrospector.invokeM(MBeanIntrospector.java:237)
        at com.sun.jmx.mbeanserver.PerInterface.getAttribute(PerInterface.java:83)
        at com.sun.jmx.mbeanserver.MBeanSupport.getAttribute(MBeanSupport.java:206)
        at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:647)
        ... 31 more
2017-07-29 10:36:06,231 ERROR org.apache.hadoop.jmx.JMXJsonServlet: getting attribute NamenodeAddresses of Hadoop:service=DataNode,name=DataNodeInfo threw an exception
javax.management.RuntimeMBeanException: java.lang.NullPointerException
2017-07-31 14:49:41,561 ERROR org.apache.hadoop.hdfs.server.datanode.DataNode: <datanodename>:50010:DataXceiver error processing WRITE_BLOCK operation src: /Y.Y.Y.Y:43298 dst: /X.X.X.X:50010 java.io.IOException: Not ready to serve the block pool, BP-939287337-X.X.X.X-1484085163925.
        at org.apache.hadoop.hdfs.server.datanode.DataXceiver.checkAndWaitForBP(DataXceiver.java:1284)
        at org.apache.hadoop.hdfs.server.datanode.DataXceiver.checkAccess(DataXceiver.java:1292)
        at org.apache.hadoop.hdfs.server.datanode.DataXceiver.writeBlock(DataXceiver.java:624)
        at org.apache.hadoop.hdfs.protocol.datatransfer.Receiver.opWriteBlock(Receiver.java:169)
        at org.apache.hadoop.hdfs.protocol.datatransfer.Receiver.processOp(Receiver.java:106)
        at org.apache.hadoop.hdfs.server.datanode.DataXceiver.run(DataXceiver.java:246)
        at java.lang.Thread.run(Thread.java:745)

Some Important configurations of my cluster:

yarn.nodemanager.resource.memory-mb - 12GB yarn.scheduler.maximum-allocation-mb - 16GB mapreduce.map.memory.mb - 4GB mapreduce.reduce.memory.mb - 4GB mapreduce.map.java.opts.max.heap - 3GB mapreduce.reduce.java.opts.max.heap - 3GB namenode_java_heapsize - 6GB secondarynamenode_java_heapsize - 6GB dfs_datanode_max_locked_memory - 3GB

dfs blocksize - 128 MB

Can anyone please help me?

Thanks,

Shilpa