Your Hadoop cluster contains nodes in three racks. You have NOT configured the dfs.hosts
property in the NameNode’s configuration file. What results?
A.
No new nodes can be added to the cluster until you specify them in the dfs.hosts file
B.
Presented with a blank dfs.hosts property, the NameNode will permit DatNode specified in
mapred.hosts to join the cluster
C.
Any machine running the DataNode daemon can immediately join the cluster
D.
The NameNode will update the dfs.hosts property to include machine running DataNode
daemon on the next NameNode reboot or with the command dfsadmin -refreshNodes