HDFS NFS

HDFS NFS Gateway Introduction:

• NFS is a distributed file system protocol.
• Allows access to files on a remote computer similar to how local file system is accessed.
• The DFSClient is inside the NFS Gateway daemon(nfs3), therefore, the DFSClient is part of the NFS Gateway.
•  HDFS NFS Gateway allows HDFS to be accessed using the NFS protocol.
• All HDFS commands are supported from listing files,copying,,moving,creating and removing directories.
• The NFS Gateway can run on any node(Datanode,NameNode or a Client Node/EdgeNode).
• The NFS Gateway has two daemons,the portmap and the nfs3.

• NFS Client: The number of application users doing the writing and the number of files being loaded concurrently define the workload.
• DSF Client: Multiple threads are used to process multiple files.DFSClient averages 30 MB/S writes.
• NFS Gateway: Multiple NFS Gateways can be created for scalability.

Advantages:

• Browsing,Downloading,Uploading from HDFS
• Streaming data directly to HDFS.
• With HDP2.x file append is supported so that users can stream data directly to HDFS but Random writes are not supported till HDP2.2 but HDP2.3.4 is supporting Random writes as well.

Limitations:

• HDFS is a read-only file system whth append capabilities.
• NFSv3 is a stateless environment.
• After an ideal period the files will be closed.

Issues:
1) NFS is up and running at commend line but it's not showing in Ambari.