[ https://issues.apache.org/jira/browse/HDFS-4558?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13595444#comment-13595444 ]
Junping Du commented on HDFS-4558: ---------------------------------- The conf in running balancer is not initialized well so left as a null value. I will deliver a patch to fix it. > start balancer failed with NPE > ------------------------------ > > Key: HDFS-4558 > URL: https://issues.apache.org/jira/browse/HDFS-4558 > Project: Hadoop HDFS > Issue Type: Bug > Components: balancer > Reporter: wenwupeng > Assignee: Junping Du > Priority: Critical > Fix For: 1.2.0 > > > start balancer failed with NPE > File this issue to track for QE and dev take a look > balancer.log: > 2013-03-06 00:19:55,174 ERROR > org.apache.hadoop.hdfs.server.balancer.Balancer: > java.lang.NullPointerException > at > org.apache.hadoop.hdfs.server.namenode.BlockPlacementPolicy.getInstance(BlockPlacementPolicy.java:165) > at > org.apache.hadoop.hdfs.server.balancer.Balancer.checkReplicationPolicyCompatibility(Balancer.java:799) > at org.apache.hadoop.hdfs.server.balancer.Balancer.<init>(Balancer.java:808) > at org.apache.hadoop.hdfs.server.balancer.Balancer.main(Balancer.java:831) > Balancer.java > private void checkReplicationPolicyCompatibility(Configuration conf) > throws UnsupportedActionException { > if (!(BlockPlacementPolicy.getInstance(conf, null, null) <== here > instanceof BlockPlacementPolicyDefault)) > { throw new UnsupportedActionException( "Balancer without > BlockPlacementPolicyDefault"); } > } -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira