[YARN-9967] Fix NodeManager failing to start when Hdfs Auxillary Jar is set

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 3.3.0
• Component/s: auxservices, nodemanager
• Assignee: Tarun Parimi
• Reporter: Prabhu Joseph
• Created: 12/Nov/19 13:10
• Updated: 24/Dec/21 02:14
• Resolved: 24/Dec/21 02:14

Description

Loading an auxiliary jar from a Hdfs location on a node manager fails with ClassNotFound Exception

2019-11-08 03:59:49,256 INFO org.apache.hadoop.util.ApplicationClassLoader: classpath: []
2019-11-08 03:59:49,256 INFO org.apache.hadoop.util.ApplicationClassLoader: system classes: [java., javax.accessibility., javax.activation., javax.activity., javax.annotation., javax.annotation.processing., javax.crypto., javax.imageio., javax.jws., javax.lang.model., -javax.management.j2ee., javax.management., javax.naming., javax.net., javax.print., javax.rmi., javax.script., -javax.security.auth.message., javax.security.auth., javax.security.cert., javax.security.sasl., javax.sound., javax.sql., javax.swing., javax.tools., javax.transaction., -javax.xml.registry., -javax.xml.rpc., javax.xml., org.w3c.dom., org.xml.sax., org.apache.commons.logging., org.apache.log4j., -org.apache.hadoop.hbase., org.apache.hadoop., core-default.xml, hdfs-default.xml, mapred-default.xml, yarn-default.xml]
2019-11-08 03:59:49,257 INFO org.apache.hadoop.service.AbstractService: Service org.apache.hadoop.yarn.server.nodemanager.containermanager.AuxServices failed in state INITED
java.lang.ClassNotFoundException: org.apache.auxtest.AuxServiceFromHDFS
	at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
	at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:335)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
	at org.apache.hadoop.util.ApplicationClassLoader.loadClass(ApplicationClassLoader.java:189)
	at org.apache.hadoop.util.ApplicationClassLoader.loadClass(ApplicationClassLoader.java:157)
	at java.lang.Class.forName0(Native Method)
	at java.lang.Class.forName(Class.java:348)
	at org.apache.hadoop.yarn.server.nodemanager.containermanager.AuxiliaryServiceWithCustomClassLoader.getInstance(AuxiliaryServiceWithCustomClassLoader.java:169)
	at org.apache.hadoop.yarn.server.nodemanager.containermanager.AuxServices.serviceInit(AuxServices.java:270)
	at org.apache.hadoop.service.AbstractService.init(AbstractService.java:164)
	at org.apache.hadoop.service.CompositeService.serviceInit(CompositeService.java:108)
	at org.apache.hadoop.yarn.server.nodemanager.containermanager.ContainerManagerImpl.serviceInit(ContainerManagerImpl.java:321)
	at org.apache.hadoop.service.AbstractService.init(AbstractService.java:164)
	at org.apache.hadoop.service.CompositeService.serviceInit(CompositeService.java:108)
	at org.apache.hadoop.yarn.server.nodemanager.NodeManager.serviceInit(NodeManager.java:478)
	at org.apache.hadoop.service.AbstractService.init(AbstractService.java:164)
	at org.apache.hadoop.yarn.server.nodemanager.NodeManager.initAndStartNodeManager(NodeManager.java:936)
	at org.apache.hadoop.yarn.server.nodemanager.NodeManager.main(NodeManager.java:1016)

Repro:

1. Prepare a custom auxiliary service jar and place it on hdfs

[hdfs@yarndocker-1 yarn]$ cat TestShuffleHandler2.java 
package org;
import org.apache.hadoop.yarn.server.api.AuxiliaryService;
import org.apache.hadoop.yarn.server.api.ApplicationInitializationContext;
import org.apache.hadoop.yarn.server.api.ApplicationTerminationContext;
import java.nio.ByteBuffer;

public class TestShuffleHandler2 extends AuxiliaryService {
    public static final String MAPREDUCE_TEST_SHUFFLE_SERVICEID = "test_shuffle2";
    public TestShuffleHandler2() {
      super("testshuffle2");
    }
    @Override
    public void initializeApplication(ApplicationInitializationContext context) {
    }
    @Override
    public void stopApplication(ApplicationTerminationContext context) {
    }
    @Override
    public synchronized ByteBuffer getMetaData() {
      return ByteBuffer.allocate(0); 
    }
  }
  
[hdfs@yarndocker-1 yarn]$ javac -d . -cp `hadoop classpath` TestShuffleHandler2.java 
[hdfs@yarndocker-1 yarn]$ jar cvf auxhdfs.jar org/
[hdfs@yarndocker-1 mapreduce]$ hadoop fs -mkdir /AUX
[hdfs@yarndocker-1 mapreduce]$ hadoop fs -put /tmp/auxhdfs.jar /AUX
[hdfs@yarndocker-1 mapreduce]$ hadoop fs -chmod 777 /AUX
[hdfs@yarndocker-1 mapreduce]$ hadoop fs -chmod 600 /AUX/auxhdfs.jar
[hdfs@yarndocker-1 mapreduce]$ hadoop fs -chown -R yarn:hadoop  /AUX

2. Configure YARN NodeManager (yarn-site.xml) to pick from Hdfs

      <property>
        <name>yarn.nodemanager.aux-services</name>
        <value>auxhdfs</value>
      </property>

      <property>
        <name>yarn.nodemanager.aux-services.auxhdfs.class&amp;lt;/name>
        <value>org.TestShuffleHandler2</value>
      </property>
	  	  
      <property>
        <name>yarn.nodemanager.aux-services.auxhdfs.remote-classpath</name>
        <value>/AUX/auxhdfs.jar</value>
      </property>

 
YARN-9965 issue is applicable for branch-3.2 and trunk (with yarn.nodemanager.aux-services.auxhdfs.system-classes configured) where NM runs fine on first time and not on subsequent restart.

This issue is applicable for trunk where NM fails to start any attempt without yarn.nodemanager.aux-services.auxhdfs.system-classes. This was an optional config in branch-3.2. YARN-9075 has set the configured custom class as a system class by default which caused the ClassNotFoundException as this class won't be in system class loader.

AuxServices#getSystemClasses has to return Null if not configured 

  private static String[] getSystemClasses(AuxServiceRecord service, String
      className) {
    AuxServiceConfiguration serviceConf =
        service.getConfiguration();
    if (serviceConf != null && serviceConf.getProperty(SYSTEM_CLASSES) != null) {
      return StringUtils.split(serviceConf.getProperty(SYSTEM_CLASSES));
    }
    return null;
  }

 

Issue Links

• is caused by: YARN-9075 Dynamically add or remove auxiliary services
• is duplicated by: YARN-11053 AuxService should not use class name as default system classes
• is duplicated by: YARN-11030 ClassNotFoundException when aux service class is loaded from customized classpath
• relates to: YARN-9965 Fix NodeManager failing to start on subsequent times when Hdfs Auxillary Jar is set