What's new in NFS v4.2?

NFS (Network File System) version 4.2 is an extension of the NFS protocol used for sharing files and directories over a network. It builds upon the features and improvements introduced in NFSv4.1 and adds several enhancements. Features and improvements introduced in NFSv4.2:

COMPOUND Operations: NFSv4.2 introduces the concept of "COMPOUND" operations, which allows multiple NFS operations to be combined into a single request, reducing the overhead associated with individual requests. This can improve performance and reduce latency in certain scenarios.

Server-Side Copy (SSC): One of the significant enhancements in NFSv4.2 is the introduction of server-side copy support. This feature allows the server to efficiently perform file copies without the need to transfer data over the network. It can significantly improve the performance of copy operations, especially for large files.

Parallel NFS (pNFS): While pNFS was introduced in NFSv4.1, NFSv4.2 includes updates to pNFS to improve scalability and performance. pNFS allows clients to access storage devices directly, enabling parallel access to data and distributed storage solutions.

Mandatory and Advisory Access Control Lists (ACLs): NFSv4.2 adds support for both mandatory and advisory ACLs. Mandatory ACLs are used for enforcing access control decisions, while advisory ACLs provide additional permissions information.

Data Server Namespace (DSN): DSN is an extension to pNFS that allows clients to discover the layout type of a file without actually opening the file. This can be useful for clients to determine how to access and manage files efficiently.

Secure NFS (krb5i and krb5p): NFSv4.2 enhances security by introducing two new security flavors, krb5i (integrity protection) and krb5p (privacy protection), which can be used with the Kerberos authentication mechanism.

Security Labeling: NFSv4.2 includes support for security labeling, which can be used for mandatory access control (MAC) security policies. This allows for the association of security labels with files and directories.

It's worth noting that the adoption of NFSv4.2 may vary among NFS implementations and organizations. As with any network protocol, it's essential to ensure compatibility and support for NFSv4.2 in both the client and server components when considering its deployment in a specific environment.