Return-Path: linux-nfs-owner@vger.kernel.org Received: from fieldses.org ([174.143.236.118]:53345 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753738Ab1LLUsj (ORCPT ); Mon, 12 Dec 2011 15:48:39 -0500 Date: Mon, 12 Dec 2011 15:48:38 -0500 From: "J. Bruce Fields" To: Frank van Maarseveen Cc: Linux NFS mailing list Subject: Re: NFS - lock failover Message-ID: <20111212204838.GD20826@fieldses.org> References: <20111201172415.GA27626@janus> <20111209103646.GA1061@janus> <20111212195613.GC20826@fieldses.org> <20111212203027.GA5068@janus> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20111212203027.GA5068@janus> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Mon, Dec 12, 2011 at 09:30:27PM +0100, Frank van Maarseveen wrote: > On Mon, Dec 12, 2011 at 02:56:13PM -0500, J. Bruce Fields wrote: > > On Fri, Dec 09, 2011 at 11:36:46AM +0100, Frank van Maarseveen wrote: > > > On Thu, Dec 01, 2011 at 06:24:16PM +0100, Frank van Maarseveen wrote: > > > > On Thu, Dec 01, 2011 at 07:07:22PM +0200, Pavel A wrote: > > > > > Hi everyone! > > > > > > > > > > I was trying not to create new topics, but it seems that posting to an > > > > > old one doesn't bring it up. Here is the original topic I'm referring > > > > > to: http://comments.gmane.org/gmane.linux.nfs/13108 > > > > > > > > > > I'm building an A/A cluster using NFS v3 and local file systems, and > > > > > looking for > > > > > efficient ways for failover (for now I have to restart nfs-kernel-server on > > > > > Takeover node to be able to initiate grace period), so the discussed solutions > > > > > are very interesting to me. > > > > > > > > > > Now (4 years after) in current nfs-utils packages (v. 1.2.2-4 and later) I can > > > > > see that the ability to release locks was really implemented and is > > > > > working well > > > > > (I mean interfaces /proc/fs/nfsd/unlock_ip and > > > > > /proc/fs/nfsd/unlock_filesystem), > > > > > but how about reacquiring locks on the node, share migrates to? - I've been > > > > > going through various mailing lists and found a lot of discussions on the topic > > > > > (also dated mainly 2007), but don't seem to find any rpc-based mechanism or > > > > > interface like /proc/fs/nfsd/nlm_set_grace to do that, was it ever made? > > > > > > > > I've posted a patch some time ago implementing > > > > /proc/fs/nfsd/relock_filesystem: > > > > > > > > http://permalink.gmane.org/gmane.linux.nfs/42360 > > > > http://permalink.gmane.org/gmane.linux.nfs/42361 > > > > http://permalink.gmane.org/gmane.linux.nfs/42362 > > > > > > Can this patch be scheduled for inclusion in mainline (3.3)? > > > > Could you resend and I'll take another look? > > I'll check it again but except for one fuzz it should still apply on > 3.2-rc. Patch offsets and an incidental fuzz is sometimes informative > about possible conflict areas. It has been verified on 3.0 and 3.1 Thanks. It would be helpful to have them resent in any case. > > But this should really be fixed to handle v4 locks as well. > > Why do you think it doesn't? The fact that unlock_* doesn't. Looking at it.... I suppose that doesn't matter as much on the grace-period starting side. How much use does that have on its own? --b.