How can we exclude some data nodes only from one namespace in hdfs federation?

Question

I was checking the hadoop federation. Here the data nodes are common, only namespace will be different. How can we exclude some datanodes only from one namespace.

Answer 1

In decommissioning the nodes that need to be decommissioned are added to the exclude file at all of the Namenodes. Each Namenode decommissions its Block Pool. When all the Namenodes finish decommissioning a Datanode, the Datanode is considered decommissioned.

For more details, you can have a look at: https://hadoop.apache.org/docs/r2.7.2/hadoop-project-dist/hadoop-hdfs/Federation.html#Decommissioning

Answer 2

You can just decommissioning a DataNode from one of the Namespace.