I have confirmed that it is the tmpfs filesystem (i.e. /ramdisk) that nfs won't export/mount. Also unionfs won't export/mount (I created two directories on a hard-drive & made them into a union in a 3rd directory on the hard drive, exported it & then got the 'permission denied' error message). This really needs to be clearly documented, particularly for newbies - it would have taken a lot of trial & error to sort this out had I not had the help from curga & chaostic. _ To summarise - how to get nfs working on dsl with the least hassle NOT SECURE! (read the nfs-howto to set secure options):
nfs won't work with tmpfs - this is any directory/file found listed in the /ramdisk directory for dsl
nfs won't work with unionfs - any directory listed by the listu command
(note: there are some exceptions to the above sweeping statements - see at the bottom of this post)
On the server:
load nfs-kernel-server.dsl extension
as root (either root terminal, emelfm as superuser or sudo in user terminal) do the following:
list directories to be exported in /etc/exportfs e.g. to export /cdrom put the line:
On the client as root (i.e. either in a root terminal or sudo in a user terminal):
Quote
/etc/init.d/nfs-common start mount <servername>:/export /dir
where 'export' is the name of the exported directory on the server & 'dir' is the name of a directory on the client.
_
If the exported directories on the server need to be changed: edit /etc/exports & then as root execute
Quote
exportfs -rav
no need to stop/start the nfs processes
_
notes about unions:
from trying various permutations I have found the following:
I created 3 directories on a hard drive u1, u2 & ux. u1 & u2 contained files. The directories were made into a union in ux. Whilts part of the union u1 & u2 can be exported & mounted by nfs, ux cannot - i.e. the union directory cannot be mounted, but the directories contained in the union can be (so long as they don't have some other restriction, such as being on a tmpfs filesystem like /ramdisk). If u1 & u2 are made into a union in u2 then u1 exports/mounts ok, but u2 does not export/mount.Yes, this is something hidden deep in the book of darkest magicks, not in any man pages for sure. It's not even in the kernel docs about tmpfs or unionfs. But I'm sure I've read the fact about tmpfs somewhere, and unionfs is by experince..
original here.