shared NFS root filesystems

[Robert Anderson]

>Anybody know how I can serve the same filesystem to
>multiple NFS clients as their root?  The problem I'm
>anticipating is that each client would assume it had
>that filesystem to itself and overwrite modifications
>already made by other clients.  I can imagine various
>hax and trickery I might commit while attempting
>to solve this problem but I hope not reinvent any wheels...

I don't think you really want to.  Years ago I setup a diskless linux
cluster where all the disk space was served from a common server.  At
that time what I came up with was a mounted root unique to each client
with less than 15MB per client.  They all mounted the same /usr and
/home partitions, but had there own / with configurations and /var &
/tmp.  The unique partition for each was actually a copy of one of
them, they just each had exclusive access to modify it without
clobbering the others.  

Our cluster booted off of a floppy and then mounted root as nfs.  If
you put CDROM's in the clients you might be able to do the same thing
but use a large ramdisk for the unique roots.  If you really need to
not have unique roots the only way I can think of is using a ramdisk
for the clients and them mount your common file systems.

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 Robert E. Anderson  		 	email: rea at sr.unh.edu
 Systems Programmer			phone: (603) 862-3489
 UNH Research Computing Center		  fax: (603) 862-1761
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