Hi All , We are in the situation to balance the cluster data since median reached 98% .. I started balancer as below
Hadoop Version: Hadoop 2.4.1 /apache/hadoop/sbin/start-balancer.sh -threshold 30 Once i start balancer it goes will for first 8-10 minutes of time.. Balancer was moving so quickly first 10 minutes.. Not sure whats happening in the cluster after sometime ( say 10 minz ) , balancer is almost stuck . Log excerpts : 2016-09-08 04:58:15,653 INFO org.apache.hadoop.hdfs.server.balancer.Balancer: Successfully moved blk_-5830766563502877304_1279767737 with size=134217728 from 10.103.21.27:1004 to 10.142.21.56:1004 through 10.103.21.27:1004 2016-09-08 04:59:14,426 INFO org.apache.hadoop.hdfs.server.balancer.Balancer: Successfully moved blk_2601479900_1104500421142 with size=268435456 from 10.103.84.51:1004 to 10.142.18.27:1004 through 10.103.84.16:1004 2016-09-08 05:01:15,037 INFO org.apache.hadoop.hdfs.server.balancer.Balancer: Successfully moved blk_3073791211_1104972921837 with size=268435456 from 10.103.21.27:1004 to 10.142.21.56:1004 through 10.103.21.42:1004 [05:16]:[hadoop@lvsaishdc3sn0002:~]$ date Thu Sep 8 05:16:53 GMT+7 2016 [05:16]:[hadoop@lvsaishdc3sn0002:~]$ jps 1003 Balancer 20388 Jps Last Block Mover Timestamp : 05:01 Current Timestamp : 05:16 Almost 15 minz no blocks moved by balancer .. What could be the issue here ?? Restart would help us start moving again.. It’s not event passing iteration 1 .. I found one thread discussing about the same issue: http://lucene.472066.n3.nabble.com/A-question-about-Balancer-in-HDFS-td4118505.html Pls suggest here to balance cluster .. --Senthil
