Subject: Re: nfs & union
To: None <current-users@netbsd.org>
From: Bernd Sieker <bsieker@freenet.de>
List: current-users
Date: 05/08/2002 00:44:23
On 08.05.02, 00:21:57, Hauke Fath wrote:
> At 0:13 Uhr +0300 8.5.2002, Mihai Chelaru wrote:
> >Hello,
> >
> >After doing something like:
> >
> >mount -t nfs -o union abc:/share1 /mnt
> >mount -t nfs -o union bca:/share1 /mnt
> >
> >and try ls /mnt, my kernel goes into db. Anyone aware of this ? My kernel is
> >one week old. I can provide core files if anyone interested.
> 
> Try mounting your NFS shares to 'intermediate' mount points, then
> union-mount those. I use a similar setup on a regular basis to build from
> pkgsrc and sys sources on arbitrary machines.
> 
> I found out long ago that union mounts and nfs mounts don't mix well.

I think it also only works if the nfs layer (mounted on an
intermediate mount point) is the lower layer. Trying to mount the nfs
layer "above" resulted in "operation not supported" error
messages. Mounting it "below" works fine. I have compiled a lot of
stuff with the complete toolchain (comp.tgz) mounted "below" the
normal /usr directory.

This was with a recent 1.5ZC snapshot of NetBSD/hpcmips, although I
have used union filesystems a lot even with earlier releases I had not
so far mixed nfs and union. I could never get union and nfs work
together with only a single mount command.

> 
> HTH,
> 	hauke
> 

-- 
Bernd Sieker

NetBSD:  No Windows or Gates, but lots of doors, portals and tunnels.
		-- Greywolf