<?xml version="1.0" encoding="UTF-8"?>
<rss xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:taxo="http://purl.org/rss/1.0/modules/taxonomy/" version="2.0">
  <channel>
    <title>question DataNode not connected to its NameNode (s) in Support Questions</title>
    <link>https://community.cloudera.com/t5/Support-Questions/DataNode-not-connected-to-its-NameNode-s/m-p/412754#M253673</link>
    <description>&lt;P&gt;我的服务器由于硬盘故障导致服务器强制重启，重启之后再开启 DataNode 节点就报着错误，打开datanode日志，错误日志如下：&lt;/P&gt;
&lt;P&gt;2025-10-27 09:57:18,577 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: supergroup = supergroup&lt;BR /&gt;2025-10-27 09:57:18,610 ERROR org.apache.hadoop.jmx.JMXJsonServlet: getting attribute DatanodeNetworkCounts of Hadoop:service=DataNode,name=DataNodeInfo threw an exception&lt;BR /&gt;javax.management.RuntimeMBeanException: java.lang.NullPointerException&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrow(DefaultMBeanServerInterceptor.java:839)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrowMaybeMBeanException(DefaultMBeanServerInterceptor.java:852)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:651)&lt;BR /&gt;at com.sun.jmx.mbeanserver.JmxMBeanServer.getAttribute(JmxMBeanServer.java:678)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.writeAttribute(JMXJsonServlet.java:346)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.listBeans(JMXJsonServlet.java:324)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.doGet(JMXJsonServlet.java:217)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1221)&lt;BR /&gt;at org.apache.hadoop.http.lib.StaticUserWebFilter$StaticUserFilter.doFilter(StaticUserWebFilter.java:109)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.HttpServer2$QuotingInputFilter.doFilter(HttpServer2.java:1296)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:399)&lt;BR /&gt;at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)&lt;BR /&gt;at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:767)&lt;BR /&gt;at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:230)&lt;BR /&gt;at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)&lt;BR /&gt;at org.mortbay.jetty.Server.handle(Server.java:326)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:928)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)&lt;BR /&gt;at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)&lt;BR /&gt;at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)&lt;BR /&gt;Caused by: java.lang.NullPointerException&lt;BR /&gt;at org.apache.hadoop.hdfs.server.datanode.DataNode.getDatanodeNetworkCounts(DataNode.java:1993)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)&lt;BR /&gt;at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:193)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:175)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:117)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:54)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanIntrospector.invokeM(MBeanIntrospector.java:237)&lt;BR /&gt;at com.sun.jmx.mbeanserver.PerInterface.getAttribute(PerInterface.java:83)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanSupport.getAttribute(MBeanSupport.java:206)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:647)&lt;BR /&gt;... 31 more&lt;BR /&gt;2025-10-27 09:57:18,610 INFO org.apache.hadoop.ipc.CallQueueManager: Using callQueue: class java.util.concurrent.LinkedBlockingQueue queueCapacity: 300&lt;BR /&gt;2025-10-27 09:57:18,621 ERROR org.apache.hadoop.jmx.JMXJsonServlet: getting attribute NamenodeAddresses of Hadoop:service=DataNode,name=DataNodeInfo threw an exception&lt;BR /&gt;javax.management.RuntimeMBeanException: java.lang.NullPointerException&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrow(DefaultMBeanServerInterceptor.java:839)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrowMaybeMBeanException(DefaultMBeanServerInterceptor.java:852)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:651)&lt;BR /&gt;at com.sun.jmx.mbeanserver.JmxMBeanServer.getAttribute(JmxMBeanServer.java:678)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.writeAttribute(JMXJsonServlet.java:346)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.listBeans(JMXJsonServlet.java:324)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.doGet(JMXJsonServlet.java:217)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1221)&lt;BR /&gt;at org.apache.hadoop.http.lib.StaticUserWebFilter$StaticUserFilter.doFilter(StaticUserWebFilter.java:109)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.HttpServer2$QuotingInputFilter.doFilter(HttpServer2.java:1296)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:399)&lt;BR /&gt;at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)&lt;BR /&gt;at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:767)&lt;BR /&gt;at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:230)&lt;BR /&gt;at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)&lt;BR /&gt;at org.mortbay.jetty.Server.handle(Server.java:326)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:928)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)&lt;BR /&gt;at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)&lt;BR /&gt;at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)&lt;BR /&gt;Caused by: java.lang.NullPointerException&lt;BR /&gt;at org.apache.hadoop.hdfs.server.datanode.DataNode.getNamenodeAddresses(DataNode.java:2850)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)&lt;BR /&gt;at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:193)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:175)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:117)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:54)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanIntrospector.invokeM(MBeanIntrospector.java:237)&lt;BR /&gt;at com.sun.jmx.mbeanserver.PerInterface.getAttribute(PerInterface.java:83)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanSupport.getAttribute(MBeanSupport.java:206)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:647)&lt;BR /&gt;... 31 more&lt;BR /&gt;2025-10-27 09:57:18,623 ERROR org.apache.hadoop.jmx.JMXJsonServlet: getting attribute VolumeInfo of Hadoop:service=DataNode,name=DataNodeInfo threw an exception&lt;BR /&gt;javax.management.RuntimeMBeanException: java.lang.NullPointerException: Storage not yet initialized&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrow(DefaultMBeanServerInterceptor.java:839)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrowMaybeMBeanException(DefaultMBeanServerInterceptor.java:852)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:651)&lt;BR /&gt;at com.sun.jmx.mbeanserver.JmxMBeanServer.getAttribute(JmxMBeanServer.java:678)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.writeAttribute(JMXJsonServlet.java:346)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.listBeans(JMXJsonServlet.java:324)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.doGet(JMXJsonServlet.java:217)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1221)&lt;BR /&gt;at org.apache.hadoop.http.lib.StaticUserWebFilter$StaticUserFilter.doFilter(StaticUserWebFilter.java:109)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.HttpServer2$QuotingInputFilter.doFilter(HttpServer2.java:1296)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:399)&lt;BR /&gt;at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)&lt;BR /&gt;at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:767)&lt;BR /&gt;at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:230)&lt;BR /&gt;at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)&lt;BR /&gt;at org.mortbay.jetty.Server.handle(Server.java:326)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:928)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)&lt;BR /&gt;at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)&lt;BR /&gt;at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)&lt;BR /&gt;Caused by: java.lang.NullPointerException: Storage not yet initialized&lt;BR /&gt;at com.google.common.base.Preconditions.checkNotNull(Preconditions.java:204)&lt;BR /&gt;at org.apache.hadoop.hdfs.server.datanode.DataNode.getVolumeInfo(DataNode.java:2868)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)&lt;BR /&gt;at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:193)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:175)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:117)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:54)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanIntrospector.invokeM(MBeanIntrospector.java:237)&lt;BR /&gt;at com.sun.jmx.mbeanserver.PerInterface.getAttribute(PerInterface.java:83)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanSupport.getAttribute(MBeanSupport.java:206)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:647)&lt;BR /&gt;... 31 more&lt;BR /&gt;2025-10-27 09:57:18,625 ERROR org.apache.hadoop.jmx.JMXJsonServlet: getting attribute DiskBalancerStatus of Hadoop:service=DataNode,name=DataNodeInfo threw an exception&lt;BR /&gt;javax.management.RuntimeMBeanException: java.lang.NullPointerException&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrow(DefaultMBeanServerInterceptor.java:839)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrowMaybeMBeanException(DefaultMBeanServerInterceptor.java:852)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:651)&lt;BR /&gt;at com.sun.jmx.mbeanserver.JmxMBeanServer.getAttribute(JmxMBeanServer.java:678)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.writeAttribute(JMXJsonServlet.java:346)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.listBeans(JMXJsonServlet.java:324)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.doGet(JMXJsonServlet.java:217)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1221)&lt;BR /&gt;at org.apache.hadoop.http.lib.StaticUserWebFilter$StaticUserFilter.doFilter(StaticUserWebFilter.java:109)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.HttpServer2$QuotingInputFilter.doFilter(HttpServer2.java:1296)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:399)&lt;BR /&gt;at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)&lt;BR /&gt;at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:767)&lt;BR /&gt;at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:230)&lt;BR /&gt;at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)&lt;BR /&gt;at org.mortbay.jetty.Server.handle(Server.java:326)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:928)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)&lt;BR /&gt;at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)&lt;BR /&gt;at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)&lt;BR /&gt;Caused by: java.lang.NullPointerException&lt;BR /&gt;at org.apache.hadoop.hdfs.server.datanode.DataNode.getDiskBalancerStatus(DataNode.java:2880)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)&lt;BR /&gt;at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:193)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:175)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:117)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:54)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanIntrospector.invokeM(MBeanIntrospector.java:237)&lt;BR /&gt;at com.sun.jmx.mbeanserver.PerInterface.getAttribute(PerInterface.java:83)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanSupport.getAttribute(MBeanSupport.java:206)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:647)&lt;BR /&gt;... 31 more&lt;BR /&gt;2025-10-27 09:57:18,636 INFO org.apache.hadoop.ipc.Server: Starting Socket Reader #1 for port 50020&lt;BR /&gt;2025-10-27 09:57:18,774 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: Opened IPC server at /39.135.1.231:50020&lt;BR /&gt;2025-10-27 09:57:18,783 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: Refresh request received for nameservices: nameservice1&lt;BR /&gt;2025-10-27 09:57:18,815 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: Starting BPOfferServices for nameservices: nameservice1&lt;BR /&gt;2025-10-27 09:57:18,825 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: Block pool &amp;lt;registering&amp;gt; (Datanode Uuid unassigned) service to SHLG-TCS-MMS-12/39.135.1.254:8022 starting to offer service&lt;BR /&gt;2025-10-27 09:57:18,826 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: Block pool &amp;lt;registering&amp;gt; (Datanode Uuid unassigned) service to SHLG-TCS-MMS-08/39.135.1.250:8022 starting to offer service&lt;BR /&gt;2025-10-27 09:57:18,831 INFO org.apache.hadoop.ipc.Server: IPC Server Responder: starting&lt;BR /&gt;2025-10-27 09:57:18,832 INFO org.apache.hadoop.ipc.Server: IPC Server listener on 50020: starting&lt;BR /&gt;2025-10-27 09:57:19,098 INFO org.apache.hadoop.hdfs.server.common.Storage: Using 24 threads to upgrade data directories (dfs.datanode.parallel.volumes.load.threads.num=24, dataDirs=24)&lt;BR /&gt;2025-10-27 09:57:19,120 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/1/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,148 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/2/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,157 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/3/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,205 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/4/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,220 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/5/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,259 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/6/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,283 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/7/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,314 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/8/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,330 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/9/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,359 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/10/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,410 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/11/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,438 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/12/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,439 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/13/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;/P&gt;
&lt;P&gt;我使用的版本是cm-5.11.2 这个版本，错误日志和之前的文档一样&lt;/P&gt;
&lt;P&gt;&lt;SPAN&gt;&lt;A href="https://community.cloudera.com/t5/Support-Questions/Datanode-is-not-connecting-to-namenode-CDH-5-14-0/m-p/64924" target="_blank" rel="noopener"&gt;https://community.cloudera.com/t5/Support-Questions/Datanode-is-not-connecting-to-namenode-CDH-5-14-0/m-p/64924&lt;/A&gt;&lt;/SPAN&gt;&lt;/P&gt;
&lt;P&gt;这篇文章没有查询到被解决&lt;/P&gt;</description>
    <pubDate>Tue, 28 Oct 2025 04:09:10 GMT</pubDate>
    <dc:creator>fuchun</dc:creator>
    <dc:date>2025-10-28T04:09:10Z</dc:date>
    <item>
      <title>DataNode not connected to its NameNode (s)</title>
      <link>https://community.cloudera.com/t5/Support-Questions/DataNode-not-connected-to-its-NameNode-s/m-p/412754#M253673</link>
      <description>&lt;P&gt;我的服务器由于硬盘故障导致服务器强制重启，重启之后再开启 DataNode 节点就报着错误，打开datanode日志，错误日志如下：&lt;/P&gt;
&lt;P&gt;2025-10-27 09:57:18,577 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: supergroup = supergroup&lt;BR /&gt;2025-10-27 09:57:18,610 ERROR org.apache.hadoop.jmx.JMXJsonServlet: getting attribute DatanodeNetworkCounts of Hadoop:service=DataNode,name=DataNodeInfo threw an exception&lt;BR /&gt;javax.management.RuntimeMBeanException: java.lang.NullPointerException&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrow(DefaultMBeanServerInterceptor.java:839)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrowMaybeMBeanException(DefaultMBeanServerInterceptor.java:852)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:651)&lt;BR /&gt;at com.sun.jmx.mbeanserver.JmxMBeanServer.getAttribute(JmxMBeanServer.java:678)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.writeAttribute(JMXJsonServlet.java:346)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.listBeans(JMXJsonServlet.java:324)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.doGet(JMXJsonServlet.java:217)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1221)&lt;BR /&gt;at org.apache.hadoop.http.lib.StaticUserWebFilter$StaticUserFilter.doFilter(StaticUserWebFilter.java:109)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.HttpServer2$QuotingInputFilter.doFilter(HttpServer2.java:1296)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:399)&lt;BR /&gt;at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)&lt;BR /&gt;at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:767)&lt;BR /&gt;at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:230)&lt;BR /&gt;at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)&lt;BR /&gt;at org.mortbay.jetty.Server.handle(Server.java:326)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:928)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)&lt;BR /&gt;at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)&lt;BR /&gt;at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)&lt;BR /&gt;Caused by: java.lang.NullPointerException&lt;BR /&gt;at org.apache.hadoop.hdfs.server.datanode.DataNode.getDatanodeNetworkCounts(DataNode.java:1993)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)&lt;BR /&gt;at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:193)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:175)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:117)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:54)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanIntrospector.invokeM(MBeanIntrospector.java:237)&lt;BR /&gt;at com.sun.jmx.mbeanserver.PerInterface.getAttribute(PerInterface.java:83)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanSupport.getAttribute(MBeanSupport.java:206)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:647)&lt;BR /&gt;... 31 more&lt;BR /&gt;2025-10-27 09:57:18,610 INFO org.apache.hadoop.ipc.CallQueueManager: Using callQueue: class java.util.concurrent.LinkedBlockingQueue queueCapacity: 300&lt;BR /&gt;2025-10-27 09:57:18,621 ERROR org.apache.hadoop.jmx.JMXJsonServlet: getting attribute NamenodeAddresses of Hadoop:service=DataNode,name=DataNodeInfo threw an exception&lt;BR /&gt;javax.management.RuntimeMBeanException: java.lang.NullPointerException&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrow(DefaultMBeanServerInterceptor.java:839)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrowMaybeMBeanException(DefaultMBeanServerInterceptor.java:852)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:651)&lt;BR /&gt;at com.sun.jmx.mbeanserver.JmxMBeanServer.getAttribute(JmxMBeanServer.java:678)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.writeAttribute(JMXJsonServlet.java:346)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.listBeans(JMXJsonServlet.java:324)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.doGet(JMXJsonServlet.java:217)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1221)&lt;BR /&gt;at org.apache.hadoop.http.lib.StaticUserWebFilter$StaticUserFilter.doFilter(StaticUserWebFilter.java:109)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.HttpServer2$QuotingInputFilter.doFilter(HttpServer2.java:1296)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:399)&lt;BR /&gt;at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)&lt;BR /&gt;at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:767)&lt;BR /&gt;at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:230)&lt;BR /&gt;at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)&lt;BR /&gt;at org.mortbay.jetty.Server.handle(Server.java:326)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:928)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)&lt;BR /&gt;at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)&lt;BR /&gt;at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)&lt;BR /&gt;Caused by: java.lang.NullPointerException&lt;BR /&gt;at org.apache.hadoop.hdfs.server.datanode.DataNode.getNamenodeAddresses(DataNode.java:2850)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)&lt;BR /&gt;at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:193)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:175)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:117)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:54)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanIntrospector.invokeM(MBeanIntrospector.java:237)&lt;BR /&gt;at com.sun.jmx.mbeanserver.PerInterface.getAttribute(PerInterface.java:83)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanSupport.getAttribute(MBeanSupport.java:206)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:647)&lt;BR /&gt;... 31 more&lt;BR /&gt;2025-10-27 09:57:18,623 ERROR org.apache.hadoop.jmx.JMXJsonServlet: getting attribute VolumeInfo of Hadoop:service=DataNode,name=DataNodeInfo threw an exception&lt;BR /&gt;javax.management.RuntimeMBeanException: java.lang.NullPointerException: Storage not yet initialized&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrow(DefaultMBeanServerInterceptor.java:839)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrowMaybeMBeanException(DefaultMBeanServerInterceptor.java:852)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:651)&lt;BR /&gt;at com.sun.jmx.mbeanserver.JmxMBeanServer.getAttribute(JmxMBeanServer.java:678)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.writeAttribute(JMXJsonServlet.java:346)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.listBeans(JMXJsonServlet.java:324)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.doGet(JMXJsonServlet.java:217)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1221)&lt;BR /&gt;at org.apache.hadoop.http.lib.StaticUserWebFilter$StaticUserFilter.doFilter(StaticUserWebFilter.java:109)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.HttpServer2$QuotingInputFilter.doFilter(HttpServer2.java:1296)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:399)&lt;BR /&gt;at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)&lt;BR /&gt;at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:767)&lt;BR /&gt;at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:230)&lt;BR /&gt;at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)&lt;BR /&gt;at org.mortbay.jetty.Server.handle(Server.java:326)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:928)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)&lt;BR /&gt;at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)&lt;BR /&gt;at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)&lt;BR /&gt;Caused by: java.lang.NullPointerException: Storage not yet initialized&lt;BR /&gt;at com.google.common.base.Preconditions.checkNotNull(Preconditions.java:204)&lt;BR /&gt;at org.apache.hadoop.hdfs.server.datanode.DataNode.getVolumeInfo(DataNode.java:2868)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)&lt;BR /&gt;at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:193)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:175)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:117)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:54)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanIntrospector.invokeM(MBeanIntrospector.java:237)&lt;BR /&gt;at com.sun.jmx.mbeanserver.PerInterface.getAttribute(PerInterface.java:83)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanSupport.getAttribute(MBeanSupport.java:206)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:647)&lt;BR /&gt;... 31 more&lt;BR /&gt;2025-10-27 09:57:18,625 ERROR org.apache.hadoop.jmx.JMXJsonServlet: getting attribute DiskBalancerStatus of Hadoop:service=DataNode,name=DataNodeInfo threw an exception&lt;BR /&gt;javax.management.RuntimeMBeanException: java.lang.NullPointerException&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrow(DefaultMBeanServerInterceptor.java:839)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.rethrowMaybeMBeanException(DefaultMBeanServerInterceptor.java:852)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:651)&lt;BR /&gt;at com.sun.jmx.mbeanserver.JmxMBeanServer.getAttribute(JmxMBeanServer.java:678)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.writeAttribute(JMXJsonServlet.java:346)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.listBeans(JMXJsonServlet.java:324)&lt;BR /&gt;at org.apache.hadoop.jmx.JMXJsonServlet.doGet(JMXJsonServlet.java:217)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)&lt;BR /&gt;at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1221)&lt;BR /&gt;at org.apache.hadoop.http.lib.StaticUserWebFilter$StaticUserFilter.doFilter(StaticUserWebFilter.java:109)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.HttpServer2$QuotingInputFilter.doFilter(HttpServer2.java:1296)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.apache.hadoop.http.NoCacheFilter.doFilter(NoCacheFilter.java:45)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1212)&lt;BR /&gt;at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:399)&lt;BR /&gt;at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)&lt;BR /&gt;at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:767)&lt;BR /&gt;at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)&lt;BR /&gt;at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:230)&lt;BR /&gt;at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)&lt;BR /&gt;at org.mortbay.jetty.Server.handle(Server.java:326)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:928)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549)&lt;BR /&gt;at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)&lt;BR /&gt;at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)&lt;BR /&gt;at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)&lt;BR /&gt;at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)&lt;BR /&gt;Caused by: java.lang.NullPointerException&lt;BR /&gt;at org.apache.hadoop.hdfs.server.datanode.DataNode.getDiskBalancerStatus(DataNode.java:2880)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)&lt;BR /&gt;at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)&lt;BR /&gt;at sun.reflect.GeneratedMethodAccessor2.invoke(Unknown Source)&lt;BR /&gt;at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)&lt;BR /&gt;at java.lang.reflect.Method.invoke(Method.java:498)&lt;BR /&gt;at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:193)&lt;BR /&gt;at com.sun.jmx.mbeanserver.ConvertingMethod.invokeWithOpenReturn(ConvertingMethod.java:175)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:117)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MXBeanIntrospector.invokeM2(MXBeanIntrospector.java:54)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanIntrospector.invokeM(MBeanIntrospector.java:237)&lt;BR /&gt;at com.sun.jmx.mbeanserver.PerInterface.getAttribute(PerInterface.java:83)&lt;BR /&gt;at com.sun.jmx.mbeanserver.MBeanSupport.getAttribute(MBeanSupport.java:206)&lt;BR /&gt;at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getAttribute(DefaultMBeanServerInterceptor.java:647)&lt;BR /&gt;... 31 more&lt;BR /&gt;2025-10-27 09:57:18,636 INFO org.apache.hadoop.ipc.Server: Starting Socket Reader #1 for port 50020&lt;BR /&gt;2025-10-27 09:57:18,774 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: Opened IPC server at /39.135.1.231:50020&lt;BR /&gt;2025-10-27 09:57:18,783 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: Refresh request received for nameservices: nameservice1&lt;BR /&gt;2025-10-27 09:57:18,815 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: Starting BPOfferServices for nameservices: nameservice1&lt;BR /&gt;2025-10-27 09:57:18,825 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: Block pool &amp;lt;registering&amp;gt; (Datanode Uuid unassigned) service to SHLG-TCS-MMS-12/39.135.1.254:8022 starting to offer service&lt;BR /&gt;2025-10-27 09:57:18,826 INFO org.apache.hadoop.hdfs.server.datanode.DataNode: Block pool &amp;lt;registering&amp;gt; (Datanode Uuid unassigned) service to SHLG-TCS-MMS-08/39.135.1.250:8022 starting to offer service&lt;BR /&gt;2025-10-27 09:57:18,831 INFO org.apache.hadoop.ipc.Server: IPC Server Responder: starting&lt;BR /&gt;2025-10-27 09:57:18,832 INFO org.apache.hadoop.ipc.Server: IPC Server listener on 50020: starting&lt;BR /&gt;2025-10-27 09:57:19,098 INFO org.apache.hadoop.hdfs.server.common.Storage: Using 24 threads to upgrade data directories (dfs.datanode.parallel.volumes.load.threads.num=24, dataDirs=24)&lt;BR /&gt;2025-10-27 09:57:19,120 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/1/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,148 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/2/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,157 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/3/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,205 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/4/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,220 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/5/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,259 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/6/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,283 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/7/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,314 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/8/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,330 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/9/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,359 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/10/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,410 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/11/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,438 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/12/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;BR /&gt;2025-10-27 09:57:19,439 INFO org.apache.hadoop.hdfs.server.common.Storage: Lock on /srv/13/dfs/dn/in_use.lock acquired by nodename 36256@SHLG-BD-HDFS-06&lt;/P&gt;
&lt;P&gt;我使用的版本是cm-5.11.2 这个版本，错误日志和之前的文档一样&lt;/P&gt;
&lt;P&gt;&lt;SPAN&gt;&lt;A href="https://community.cloudera.com/t5/Support-Questions/Datanode-is-not-connecting-to-namenode-CDH-5-14-0/m-p/64924" target="_blank" rel="noopener"&gt;https://community.cloudera.com/t5/Support-Questions/Datanode-is-not-connecting-to-namenode-CDH-5-14-0/m-p/64924&lt;/A&gt;&lt;/SPAN&gt;&lt;/P&gt;
&lt;P&gt;这篇文章没有查询到被解决&lt;/P&gt;</description>
      <pubDate>Tue, 28 Oct 2025 04:09:10 GMT</pubDate>
      <guid>https://community.cloudera.com/t5/Support-Questions/DataNode-not-connected-to-its-NameNode-s/m-p/412754#M253673</guid>
      <dc:creator>fuchun</dc:creator>
      <dc:date>2025-10-28T04:09:10Z</dc:date>
    </item>
    <item>
      <title>Re: DataNode not connected to its NameNode (s)</title>
      <link>https://community.cloudera.com/t5/Support-Questions/DataNode-not-connected-to-its-NameNode-s/m-p/412755#M253674</link>
      <description>&lt;P&gt;Translation:&lt;/P&gt;
&lt;P&gt;My server was forced to restart due to a hard disk failure. After the restart, I started the DataNode node and reported an error. I opened the DataNode log and the error log was as follows: (see above)&lt;/P&gt;</description>
      <pubDate>Tue, 28 Oct 2025 04:10:01 GMT</pubDate>
      <guid>https://community.cloudera.com/t5/Support-Questions/DataNode-not-connected-to-its-NameNode-s/m-p/412755#M253674</guid>
      <dc:creator>DianaTorres</dc:creator>
      <dc:date>2025-10-28T04:10:01Z</dc:date>
    </item>
    <item>
      <title>Re: DataNode not connected to its NameNode (s)</title>
      <link>https://community.cloudera.com/t5/Support-Questions/DataNode-not-connected-to-its-NameNode-s/m-p/412757#M253676</link>
      <description>&lt;P&gt;硬盘故障，更换硬盘后，datanode可以启动成功了&lt;/P&gt;</description>
      <pubDate>Tue, 28 Oct 2025 08:53:40 GMT</pubDate>
      <guid>https://community.cloudera.com/t5/Support-Questions/DataNode-not-connected-to-its-NameNode-s/m-p/412757#M253676</guid>
      <dc:creator>fuchun</dc:creator>
      <dc:date>2025-10-28T08:53:40Z</dc:date>
    </item>
  </channel>
</rss>

