Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!lll-lcc!styx!ames!ucbcad!ucbvax!ISI.EDU!braden From: braden@ISI.EDU (Bob Braden) Newsgroups: mod.protocols.tcp-ip Subject: Re: Need information on NFS Message-ID: <8612191830.AA00835@braden.isi.edu> Date: Fri, 19-Dec-86 13:30:44 EST Article-I.D.: braden.8612191830.AA00835 Posted: Fri Dec 19 13:30:44 1986 Date-Received: Sat, 20-Dec-86 06:23:31 EST Sender: daemon@ucbvax.BERKELEY.EDU Organization: The ARPA Internet Lines: 50 Approved: tcp-ip@sri-nic.arpa Sun's NFS is NOT a good Unix Networked Filesystem. They broke some Unix semantics in the name of generality to the non-unix world. Sun claims it to be a non-unix specific design. Are we to read "not good" as "bad"? If not, what do you mean by this complaint? If so, why should we standardize a protocol which is bad for an important class of hosts? What do you see as the major problems? "Considerable work" doesn't sound right. The problem most people have cited is NFS' authentication/permission model, which is not only Unix-oriented but also perhaps inadequate. This is a hard and important issue. In fact, it has been pointed out that the assumption of globally-unique uid's and gid's is invalid in many sites even among Unix systems. Another problem is in the remote mount protocol. SUN treats it as separate, yet it seems that its functions ought to be included in any network file system standard. Another set of issues has to do with convincing ourselves that the NFS primitives have sufficient generality to provide useful service with the other file systems in the world besides Unix. That probably means generalizing the existing primitives and adding a few more. It also means providing defined hooks for extensibility. Finally, there is the issue of underlying layers. NFS assumes two other protocols, XDR and RPC. It seems desirable to define NFS independently of the lower layers, so different choices could be made in the future for these protocols (after all, that is what layering is really for). RPC, in particular, is highly doubtful in its present form as an Internet standard, as its transport-protocol mechanism seems deficient. It seems to run with MS-DOS and VMS as far as I know. So, it's not too Unix-specific. More information about the generality and completeness of these implementations would be interesting and useful. Could I do a remote mount from my SUN to our VMS machine, for example, and access any VMS file? Can the VMS machine get at any Unix file (subject to permissions)? How do permissions work? Finally, I don't know how much time you have spent on protocol committees, but every one of the existing Internet protocols represents several manyears (or more) of concentrated effort, spread out over 2-5 years. Bob Braden