pnode20 on hdfs type nfs rwrelatimevers=3rsize=1048576wsize=1048576namlen=255hardproto=tcptimeo=600retrans=2sec=sysmountaddr=1025222620mountvers=3mountport=4242mountproto=udplocal_lock=noneaddr=102522

The given line is a mount command that mounts a remote NFS share on the local system.

• pnode20:/ - The remote NFS server address and the exported share path.
• /hdfs - The local mount point where the remote share will be mounted.
• type nfs - Specifies the file system type as NFS.
• rw - Mounts the share in read-write mode.
• relatime - Updates the access time only if the previous access time is older than the modified time or when a file is opened for writing.
• vers=3 - Specifies the NFS protocol version as 3.
• rsize=1048576 - Sets the read buffer size to 1MB.
• wsize=1048576 - Sets the write buffer size to 1MB.
• namlen=255 - Limits the maximum length of file names to 255 characters.
• hard - Enables a hard mount, which means that the client will keep retrying indefinitely if the server becomes unreachable.
• proto=tcp - Specifies the transport protocol as TCP.
• timeo=600 - Sets the timeout value to 600 seconds (10 minutes).
• retrans=2 - Specifies the number of retransmissions before giving up.
• sec=sys - Specifies the security mode as system-based.
• mountaddr=10.252.226.20 - Specifies the IP address of the NFS server.
• mountvers=3 - Specifies the NFS protocol version to use for the mount operation.
• mountport=4242 - Specifies the port number on which the NFS server is listening for mount requests.
• mountproto=udp - Specifies the transport protocol for the mount operation as UDP.
• local_lock=none - Disables local file locking.
• addr=10.252.226.20 - Specifies the IP address of the NFS server.