The Network File System (NFS) is one of the first and most widely distributed file systems in the UNIX environment. It provides the ability for systems to mount file systems of other servers through the network. The rpcbind service maps Remote Procedure Call (RPC) services to the ports on which they listen. RPC processes notify rpcbind when they start, registering the ports they are listening on and the RPC program numbers they expect to serve. The client system then contacts rpcbind on the server with a particular RPC program number. The rpcbind service redirects the client to the proper port number so it can communicate with the requested service. Rationale: If the system does not export NFS shares, it is recommended that the NFS be disabled to reduce the remote attack surface. If the system does not require rpc based services, it is recommended that rpcbind be disabled to reduce the remote attack surface.