Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!gordius!johnk
From: johnk@gordian.com (John Kalucki)
Newsgroups: comp.protocols.nfs
Subject: Forcing a umount
Keywords: nfs, umount, mount, fuser
Message-ID: <118@gordius.gordian.com>
Date: 22 Mar 91 23:26:38 GMT
Sender: news@gordian.com
Reply-To: johnk@gordian.com (John Kalucki)
Organization: Gordian; Costa Mesa, CA
Lines: 34


I'm having trouble arranging my nfs links to avoid halting all of
my machines when one machine crashes. I have 6 Mips workstations
which are all intermounted, each host has the data disk of all
other hosts mounted.  All of the filesystems are mounted -soft and
all of the mountpoints are in /n/{machine}, where they should be
out of some of harm's way.

When one machine goes down, all others have difficulties, ranging
from simply freezing up to having pwd(1) timeout. This happens even
though data is not being accessed on the machine that is down (or
so I'd like to think).

I'd like to be able to umount the machine that is down, perhaps in
the same way as when Unix is being shutdown-a forceable unmount
occurs. I don't really care if any processes are confused by the
forceable unmount, I'd just like to avoid the NFS:timed out messages
(and the occasional long timeout period) to get the client
machine functional again.

Another thing I've thought of is to put each server in
/{machine}/{machine} to avoid having pwd stat the directory with
the mountpoint unless needed, but this seems quite ugly.

Also, when a server is up, but I can't unmount it, because the fs
is busy, is there an easy way to find which processes are the
offenders? I've looked at the fuser command that comes on the Mips
boxes, but it doesn't work with NFS.

Any hints?


		-John Kalucki
		johnk@gordian.com