Node roles planning in FPO mode

In the FPO mode, all nodes are IBM Storage Scale nodes, Hadoop nodes, and HDFS Transparency nodes.

Typical Cluster Planning for IBM Storage Scale FPO mode

In this figure, one node is selected as the HDFS Transparency NameNode. All the other nodes are HDFS Transparency DataNodes. Also, the HDFS Transparency NameNode can be an HDFS Transparency DataNode. Any one node can be selected as HDFS Transparency HA NameNode. The administrator must ensure that the primary HDFS Transparency NameNode and the standby HDFS Transparency NameNode are not the same node.

In this mode, Hadoop cluster must be larger than or equal to the HDFS transparency cluster.

Note: The Hadoop cluster might be smaller than HDFS transparency cluster but this configuration is not typical and not recommended. Also, the HDFS transparency cluster must be smaller than or equal to IBM Storage Scale cluster because the HDFS transparency must read and write data to the local mounted file system. Usually, in the FPO mode, the HDFS transparency cluster is equal to the IBM Storage Scale cluster.

Note: Some nodes in the IBM Storage Scale (GPFS) FPO cluster might be GPFS clients without any disks in the file system.