What are the components of HDFS and YARN ?
NameNode
- NameNode is the master node for processing metadata information for data blocks within the HDFS.
DataNode/SlaveNode
- DataNode is the node which acts as slave node to store the data, for processing and use by the NameNode.
- In addition to serving the client requests, the NameNode executes either of two following roles –
- CheckpointNode.
- BackupNode.
CheckpointNode
- It runs on a different host from the NameNode
BackupNode
- It is a read-only NameNode which contains file system metadata information excluding the block locations.
Components of YARN
ResourceManager
- This component receives processing requests and accordingly allocates to respective NodeManagers depending on processing needs.
NodeManager
- It executes tasks on each single Data Node.
