From owner-freebsd-fs@FreeBSD.ORG Mon Jun 29 23:53:52 2009 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 2EF01106564A for ; Mon, 29 Jun 2009 23:53:52 +0000 (UTC) (envelope-from rick@kiwi-computer.com) Received: from hamlet.setfilepointer.com (hamlet.SetFilePointer.com [63.224.10.2]) by mx1.freebsd.org (Postfix) with SMTP id CE79D8FC0A for ; Mon, 29 Jun 2009 23:53:51 +0000 (UTC) (envelope-from rick@kiwi-computer.com) Received: (qmail 54739 invoked from network); 29 Jun 2009 18:27:10 -0500 Received: from keira.kiwi-computer.com (HELO kiwi-computer.com) (63.224.10.3) by hamlet.setfilepointer.com with SMTP; 29 Jun 2009 18:27:10 -0500 Received: (qmail 25161 invoked by uid 2001); 29 Jun 2009 23:27:10 -0000 Date: Mon, 29 Jun 2009 18:27:10 -0500 From: "Rick C. Petty" To: Nathanael Hoyle Message-ID: <20090629232710.GA24986@keira.kiwi-computer.com> References: <4A480B8C.1060708@hoyletech.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4A480B8C.1060708@hoyletech.com> User-Agent: Mutt/1.4.2.3i Cc: freebsd-fs@freebsd.org Subject: Re: umount -f implementation X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: rick-freebsd2008@kiwi-computer.com List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 29 Jun 2009 23:53:52 -0000 On Sun, Jun 28, 2009 at 08:32:12PM -0400, Nathanael Hoyle wrote: > Rick Macklem wrote: > > > >Does that sound correct? (In other words, an I seeing a bug or a > >feature?) > > > I think the answer is probably "it's a feature, not a bug", but that > depends on your NFS mount options which you didn't give. I'd suggest > you read up on NFS soft versus hard mounts. I'm pretty sure the person working on NFSv4 for fbsd knows this difference. > I think you're seeing the > latter and expecting the former behavior. Not necessarily true. I've experienced similar behavior and I only use soft mounts (actually: "rw,soft,intr,bg,rdirplus"). In fact this bit me last week when I wanted to move the NFS export on a server. I did the move/rename, updated /etc/exports, and did a "killall -HUP mountd" on the server and I attempted variations of "mount -u" and "umount -f" on the clients. Subsequently, I had to restart most of the client machines, since: - "mount -u" returned ESTALE - "umount" returned EBUSY - "umount -f" failed, I believe with ENXIO In any case, "umount -f" absolutely has to work. What other option does an admin have? Yes, expect potential data loss and expect the umount may not return immediately (plain "umount" can take awhile too). Instead, I saw a bunch of these messages, when another process continued to write to a geli-mounted md'd file on that stale filesystem: kernel: GEOM_ELI: g_eli_read_done() failed md0.eli[READ(offset=1790541824, length=65536)] -- Rick C. Petty