From owner-freebsd-questions@FreeBSD.ORG  Tue Dec  7 06:01:39 2004
Return-Path: <owner-freebsd-questions@FreeBSD.ORG>
Delivered-To: freebsd-questions@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id E0AF716A4CE
	for <freebsd-questions@freebsd.org>;
	Tue,  7 Dec 2004 06:01:39 +0000 (GMT)
Received: from crux.i-cable.com (crux.i-cable.com [203.83.110.33])
	by mx1.FreeBSD.org (Postfix) with SMTP id A20A543D58
	for <freebsd-questions@freebsd.org>;
	Tue,  7 Dec 2004 06:01:38 +0000 (GMT)
	(envelope-from jtay@netsolutions.com.hk)
Received: (qmail 6255 invoked by uid 107); 7 Dec 2004 06:01:37 -0000
Received: from jtay@netsolutions.com.hk by crux by uid 104 with
	qmail-scanner-1.22-st-qms Clear:RC:1(218.255.91.64):SA:0(-4.9/5.0):. 
	Processed in 1.906964 secs); 07 Dec 2004 06:01:37 -0000
X-Spam-Status: No, hits=-4.9 required=5.0
Received: from cm218-255-91-64.hkcable.com.hk (HELO dev) (218.255.91.64)
  by 0 with SMTP; 7 Dec 2004 06:01:35 -0000
Message-ID: <000601c4dc22$3584f040$6901a8c0@dev>
From: "Jeremy Tay" <jtay@netsolutions.com.hk>
To: <freebsd-questions@freebsd.org>
Date: Tue, 7 Dec 2004 14:01:35 +0800
MIME-Version: 1.0
Content-Type: text/plain;
	charset="big5"
Content-Transfer-Encoding: 7bit
X-Priority: 3
X-MSMail-Priority: Normal
X-Mailer: Microsoft Outlook Express 6.00.2800.1409
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1409
Subject: Problems umount-ing dead NFS
X-BeenThere: freebsd-questions@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: User questions <freebsd-questions.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>,
	<mailto:freebsd-questions-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-questions>
List-Post: <mailto:freebsd-questions@freebsd.org>
List-Help: <mailto:freebsd-questions-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>,
	<mailto:freebsd-questions-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 07 Dec 2004 06:01:40 -0000

 
Hi everybody,

I am very confused about how to actually unmount a NFS filesystem that
has gone stray. I am currently writing a script that switches between
the main and backup servers according to their state, but when testing
it, everything seems to halt at unmounting the dead fs.

I tested it by mounting an export on a client, and then changing the
server's IP address or switching it completely off. When umount (or
umount -f) is called on the client to detach the dead filesystem before
mounting the export of the backup server, it stood still.

Some googling informed me that rebooting is the only way to get rid of
the stale fs but others say that a umount -f should free up the mount if
it is mounted soft. The flags I use are -3isl -R1 -t5 -D5 -r32768
-w32768 and still I can't unmount it.

Please give me a hand... any help would be appreciated.

- Jeremy