Plan the data movement across disks
A Disk Balancer plan identifies the amount of data that should move between the disks of a specified DataNode. The plan contains move steps, where each move step specifies the source and destination disks for data movement and the number of bytes to move.
hdfs-site.xml to true.
Run the
hdfs diskbalancer -plan command by specifying the path to
the DataNode.
For example,
hdfs diskbalancer -plan node1.mycluster.com.The specified command generates the following two JSON documents as output
in the HDFS namespace:
<nodename>.before.json
that indicates the state of the cluster before running Disk Balancer, and
<nodename>.plan.json that details the
data movement plan for the DataNode. By default, the JSON documents are placed in
the following location:
/system/diskbalancer/<Creation_Timestamp>. Here,
<Creation_Timestamp> indicates the folder named according
to the date and time of creation of the JSON documents.
