Minor Description
Have seen this during unit testing, this ticket is opened to safely unregister MBeans for SCMConnectionManager.
2018-09-19 22:18:14,059 WARN util.MBeans (MBeans.java:unregister(145)) - Error unregistering Hadoop:service=HddsDatanode,name=SCMConnectionManager-5 javax.management.InstanceNotFoundException: Hadoop:service=HddsDatanode,name=SCMConnectionManager-5 at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.getMBean(DefaultMBeanServerInterceptor.java:1095) at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.exclusiveUnregisterMBean(DefaultMBeanServerInterceptor.java:427) at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.unregisterMBean(DefaultMBeanServerInterceptor.java:415) at com.sun.jmx.mbeanserver.JmxMBeanServer.unregisterMBean(JmxMBeanServer.java:546) at org.apache.hadoop.metrics2.util.MBeans.unregister(MBeans.java:143) at org.apache.hadoop.ozone.container.common.statemachine.SCMConnectionManager.close(SCMConnectionManager.java:194) at org.apache.hadoop.ozone.container.common.statemachine.DatanodeStateMachine.close(DatanodeStateMachine.java:232) at org.apache.hadoop.ozone.container.common.statemachine.DatanodeStateMachine.stopDaemon(DatanodeStateMachine.java:343) at org.apache.hadoop.ozone.HddsDatanodeService.stop(HddsDatanodeService.java:211) at org.apache.hadoop.ozone.MiniOzoneClusterImpl.restartHddsDatanode(MiniOzoneClusterImpl.java:237) at org.apache.hadoop.ozone.MiniOzoneClusterImpl.restartHddsDatanode(MiniOzoneClusterImpl.java:263) at org.apache.hadoop.hdds.scm.pipeline.TestNodeFailure.testPipelineFail(TestNodeFailure.java:119) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44) at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17) at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229) at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26) at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27) at org.junit.runners.ParentRunner.run(ParentRunner.java:309) at org.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:365) at org.apache.maven.surefire.junit4.JUnit4Provider.executeWithRerun(JUnit4Provider.java:273) at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:238) at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:159) at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:379) at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:340) at org.apache.maven.surefire.booter.ForkedBooter.execute(ForkedBooter.java:125) at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:413) 2018-09-19 22:18:14,059 INFO ozoneimpl.OzoneContainer (OzoneContainer.java:stop(149)) - Attempting to stop container services.