Is rpcbind needed for an NFS client?

The NFS client uses rpcbind service on server to discover the port number used by nfsd.

More over, for clients of nfs v2 and v3, an additional rpc-statd service is used to manage locks. As rpc-statd runs on the client, a rpcbind should run on the client to let nfs servers to discover on which port rpc-statd listens.

Thus, for client that uses nfs v4, the rpcbind, rpc-statd and rpc-statd-notify services can be disabled. This can required modifying some .service files.

IOW - The rpcbind service is needed by nfs clients that use v2 and v3, as it required for file locking, and can be disabled for nfs v4 clients, as locking is a part of the NFSv4.0 protocol.