[HDFS-5524] NPE during Namenode startup in Server#getNumConnections

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Duplicate
• Affects Version/s: 3.0.0-alpha1
• Component/s: namenode
• Assignee: Unassigned
• Reporter: Andrew Wang
• Created: 19/Nov/13 00:44
• Updated: 12/May/16 18:13
• Resolved: 19/Nov/13 00:57

Description

Saw this stacktrace while starting up a trunk namenode, maybe a race between starting the RPC server and the metrics system?

13/11/18 14:49:32 ERROR lib.MethodMetric: Error invoking method numOpenConnections
java.lang.reflect.InvocationTargetException
    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 org.apache.hadoop.metrics2.lib.MethodMetric$2.snapshot(MethodMetric.java:110)
        at org.apache.hadoop.metrics2.lib.MethodMetric.snapshot(MethodMetric.java:141)
        at org.apache.hadoop.metrics2.lib.MetricsRegistry.snapshot(MetricsRegistry.java:387)
        at org.apache.hadoop.metrics2.lib.MetricsSourceBuilder$1.getMetrics(MetricsSourceBuilder.java:88)
        at org.apache.hadoop.metrics2.impl.MetricsSourceAdapter.getMetrics(MetricsSourceAdapter.java:194)
        at org.apache.hadoop.metrics2.impl.MetricsSourceAdapter.updateJmxCache(MetricsSourceAdapter.java:171)
        at org.apache.hadoop.metrics2.impl.MetricsSourceAdapter.getMBeanInfo(MetricsSourceAdapter.java:150)
        at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getNewMBeanClassName(DefaultMBeanServerInterceptor.java:333)
        at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.registerMBean(DefaultMBeanServerInterceptor.java:319)
        at com.sun.jmx.mbeanserver.JmxMBeanServer.registerMBean(JmxMBeanServer.java:522)
        at org.apache.hadoop.metrics2.util.MBeans.register(MBeans.java:58)
        at org.apache.hadoop.metrics2.impl.MetricsSourceAdapter.startMBeans(MetricsSourceAdapter.java:219)
        at org.apache.hadoop.metrics2.impl.MetricsSourceAdapter.start(MetricsSourceAdapter.java:95)
        at org.apache.hadoop.metrics2.impl.MetricsSystemImpl.registerSource(MetricsSystemImpl.java:242)
        at org.apache.hadoop.metrics2.impl.MetricsSystemImpl.register(MetricsSystemImpl.java:222)
        at org.apache.hadoop.ipc.metrics.RpcMetrics.create(RpcMetrics.java:57)
        at org.apache.hadoop.ipc.Server.<init>(Server.java:2112)
        at org.apache.hadoop.ipc.RPC$Server.<init>(RPC.java:902)
        at org.apache.hadoop.ipc.ProtobufRpcEngine$Server.<init>(ProtobufRpcEngine.java:507)
        at org.apache.hadoop.ipc.ProtobufRpcEngine.getServer(ProtobufRpcEngine.java:480)
        at org.apache.hadoop.ipc.RPC$Builder.build(RPC.java:746)
        at org.apache.hadoop.hdfs.server.namenode.NameNodeRpcServer.<init>(NameNodeRpcServer.java:288)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.createRpcServer(NameNode.java:512)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:492)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:688)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:673)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1271)
        at org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1337)
    Caused by: java.lang.NullPointerException
        at org.apache.hadoop.ipc.Server.getNumOpenConnections(Server.java:2434)
        at org.apache.hadoop.ipc.metrics.RpcMetrics.numOpenConnections(RpcMetrics.java:74)
        ... 32 more