Rebalancing HDFS
HDFS provides a “balancer” utility to help balance the blocks across DataNodes in the cluster. To initiate a balancing process, follow these steps:
In Ambari Web, browse to Services > HDFS > Summary.
Click Service Actions, and then click Rebalance HDFS.
Enter the Balance Threshold value as a percentage of disk capacity.
Click Start.
You can monitor or cancel a rebalance process by opening the Background Operations window in Ambari.
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