The server network configuration ensures that appropriate clients can negotiate with it through any firewall system. The client machine requests access to exported data, typically by issuing a mount command. (The client asks the server (rpcbind) which port the NFS server is using, the client connects to the NFS server (nfsd), nfsd passes the request to mountd) If all goes well, users on the client machine can then view and interact with mounted filesystems on the server within the parameters permitted.