NFSv2

Network File System version 2, commonly known as NFSv2, is an early protocol for distributed file system access developed by Sun Microsystems. It allows a client computer to access files over a network in a manner that appears to be local storage. NFSv2 was released in the late 1980s and became a widely adopted standard for sharing files across different Unix-based systems.

The protocol operates on a client-server model. The NFS server exports directories that clients can then mount. Once mounted, clients can read, write, and execute files on the server as if they were on their own disk. NFSv2 uses Remote Procedure Calls (RPC) to communicate between the client and server, primarily over UDP.

A key characteristic of NFSv2 is its stateless design on the server side. This means the server does not maintain information about the state of client connections. While this simplified server implementation, it also presented challenges for handling file locking and crash recovery. Clients had to manage their own state.

NFSv2 has limitations, notably its lack of support for larger file sizes and its performance characteristics compared to later versions. It also had less robust security features. Despite these drawbacks, its widespread adoption in its time contributed significantly to the development of networked computing environments. Modern systems generally use newer versions of NFS like NFSv3, NFSv4, and its subsequent revisions, which address many of NFSv2's limitations.