Re: mount -t nfs4 fails, but mount -t nfs succeeds [SOLVED]

On Thu, 2012-04-26 at 13:17 -0700, Jonathan Ryshpan wrote: What a lot of comments! This deserves a reply at length. I state a lot of things below as fact. But snce I'm still pretty ignorant about nfs4 some of them may not be true. Those who know please put in corrections; and we may arrive at the truth about something that's still pretty murky to most people. Comments on particular postings follow. Nfs4 exports a tree of directories from a server to a client. The root of the tree must be the root of the filesystem on the host and the line containing it in /etc/exports must contain the option fsid=root (alternately fsid=0). If such a line appears in /etc/exports then any directory on the server can be exported, and the client can mount any directory appearing there. Nfs4 works through a firewall, provided that port port 2049/tcp is opened; nfs3 requires that the firewall be (completely) disabled. "showmount -e <host>" doesn't work through a firewall, it appears to be associated with nfs3. There is no utility like it that works through port 2049/tcp; administrators have to know which files are available via the nfs4 port from which servers. There's an intro to setting up nfs4 (link from Ed Greshko) that states that the fsid=0 option can be applied to any directory, and then other directories to be exported should be (bound to) subdirectories of this one; but I haven't been able to get it to work. Funky problems: 1) If the client has an actual name or exact IP address in /etc/exports, like this line: /nfs4 amito:/(rw,fsid=0,...) or /nfs4 192.168.2.5(rw,fsid=0,...) mount attempts fail with the message "No such file or directory". 2)If the line in /etc/exports has a form like /nfs4 192.168.0.0/24(rw,fsid=0,...) mount attempts fail with the message "access denied by server". There's probably some problem with the options in the parentheses, but I've tried them all, starting with the exact ones in the intro without success. On the other hand, exporting the actual root / amito:(rw,fsid=0,..) mounts fine. I hope to be enlightened. Detailed comments follow: Michael Cronenworth <mike(a)cchtml.com&gt; wrote So it is, in a sense. But the documentation of fsid in the exports man page isn't marked as having anything in particular to do with nfs4. Quite right. But I didn't want to let exporting the root filesystem be a red herring. Veli-Pekka Kestilä <fedora(a)guagua.fi&gt; wrote The exports *syntax* is the same in nfs4 as in nfs3. There are differences in *semantics* as I explained in my note at the start of this posting. Ian Pilcher <arequipeno(a)gmail.com&gt; wrote If only... I spent most of a day Googling around before I found the article in the Arch Linux Wiki. Most of the stuff in my note at the top doesn't seem to be anywhere obvious. Robert P. J. Day <rpjday(a)crashcourse.ca&gt; wrote The example network, though a very small one (2 machines) run nfs4 only. Ed Greshko <Ed.Greshko(a)greshko.com&gt; wrote Very good reference. Kernel Guardian <kernelgardian(a)gmail.com&gt; wrote: Both systems are running Fedora-16 with all upgrades installed. Unfortunately I have made so many changes to /etc/exports and the firewall on the server that these would not be useful.