Return-Path: Received: from fieldses.org ([173.255.197.46]:32948 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752088AbcHSR1G (ORCPT ); Fri, 19 Aug 2016 13:27:06 -0400 Date: Fri, 19 Aug 2016 13:27:04 -0400 From: "J. Bruce Fields" To: NeilBrown Cc: Steve Dickson , Linux NFS Mailing list Subject: Re: [PATCH 3/8] mountd: remove 'dev_missing' checks Message-ID: <20160819172704.GJ32329@fieldses.org> References: <20160714021310.5874.22953.stgit@noble> <20160714022643.5874.84409.stgit@noble> <20160718200121.GC12304@fieldses.org> <878twx9ra3.fsf@notabene.neil.brown.name> <20160721172452.GC27148@fieldses.org> <87wpjokofy.fsf@notabene.neil.brown.name> <20160816152148.GC30124@fieldses.org> <87bn0qj1yz.fsf@notabene.neil.brown.name> <20160818135754.GA21470@fieldses.org> <8737m1im2p.fsf@notabene.neil.brown.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <8737m1im2p.fsf@notabene.neil.brown.name> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Fri, Aug 19, 2016 at 11:28:30AM +1000, NeilBrown wrote: > On Thu, Aug 18 2016, J. Bruce Fields wrote: > > > Not really arguing--I'll trust your judgement--just some random ideas: > > > > On Thu, Aug 18, 2016 at 11:32:52AM +1000, NeilBrown wrote: > >> On Wed, Aug 17 2016, J. Bruce Fields wrote: > >> > In which case what it really wants to say is "before nfs mounts" (or > >> > even "before nfs mounts of localhost"; and vice versa on shutdown). I > >> > can't tell if there's an easy way to get say that. > >> > >> I'd be happy with a difficult/complex way, if it was reliable. > >> Could we write a systemd generator which parses /etc/fstab, determines > >> all mount points which a loop-back NFS mounts (or even just any NFS > >> mounts) and creates a drop-in for nfs-server which adds > >> Before=mount-point.mount > >> for each /mount/point. > >> > >> Could that be reliable? I might try. > > > > Digging around... we've also got this callout from mount to start-statd, > > can we use something like that to make loopback nfs mounts wait on nfs > > server startup? > > An nfs mount already waits for the server to start up. The ordering > dependency between NFS mounts and the nfs-server only really matters at > shutdown, and we cannot enhance mount.nfs to wait for a negative amount > of time (also known as "time travel") D'oh, I keep forgetting that point. --b.