Return-Path: linux-nfs-owner@vger.kernel.org Received: from fieldses.org ([174.143.236.118]:55006 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752995Ab3JYOUN (ORCPT ); Fri, 25 Oct 2013 10:20:13 -0400 Date: Fri, 25 Oct 2013 10:20:12 -0400 To: Steve Dickson Cc: Jeff Layton , Linux NFS Mailing list Subject: Re: [PATCH 0/3] mountd: disabling turning off TCP listeners (v2) Message-ID: <20131025142012.GC20497@fieldses.org> References: <1382638633-6710-1-git-send-email-steved@redhat.com> <20131024144507.72aa34a8@tlielax.poochiereds.net> <526978BF.7020202@RedHat.com> <20131025074316.2affe9e9@tlielax.poochiereds.net> <526A62C1.6060803@RedHat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <526A62C1.6060803@RedHat.com> From: "J. Bruce Fields" Sender: linux-nfs-owner@vger.kernel.org List-ID: On Fri, Oct 25, 2013 at 08:23:29AM -0400, Steve Dickson wrote: > > > On 25/10/13 07:43, Jeff Layton wrote: > > On Thu, 24 Oct 2013 15:45:03 -0400 > > Steve Dickson wrote: > > > >> > >> > >> On 24/10/13 14:45, Jeff Layton wrote: > >>> On Thu, 24 Oct 2013 14:17:10 -0400 > >>> Steve Dickson wrote: > >>> > >>>> [ Here is the second try for these patches incorporating the code review..] > >>>> > >>>> Recently it was pointed out to me that the [-n | --no-tcp] flags > >>>> were broken in mountd. Sure enough they are and they broke > >>>> when nfs-utils moved to using libtirpc, which was years ago. > >>>> > >>>> Obviously nobody is using these flags since has not been > >>>> notice until now, but it seemed to me it no longer makes > >>>> any sense to have flags. We really want people to use TCP > >>>> so why should there be a way to turn it off? It should be > >>>> the opposite... They should be able to turn off UDP listeners > >>>> not TCP... > >>>> > >>>> > >>>> Steve Dickson (3): > >>>> mountd: Use protocol bit fields to turn protocols off. > >>>> mountd: Deprecate the ability to disable TCP listeners. > >>>> mountd: Add the ability to disable UDP listeners. > >>>> > >>>> support/include/rpcmisc.h | 2 +- > >>>> support/nfs/rpcmisc.c | 19 ++++++++++++++----- > >>>> support/nfs/svc_create.c | 5 +++++ > >>>> utils/mountd/mountd.c | 17 ++++++++++++----- > >>>> utils/mountd/mountd.man | 6 +++--- > >>>> 5 files changed, 35 insertions(+), 14 deletions(-) > >>>> > >>> > >>> Sorry I'm coming in late on this... > >> np... I was expecting more push back! ;-) > >> > >>> > >>> I don't think we want to remove the ability to disable TCP listeners. > >>> > >>> Why, you ask? We've been on a multi-year effort to move people to > >>> NFSv4, and with that, there's no reason to have mountd listen on the > >>> network at all. > >> True... > >> > >>> > >>> So personally, I think it would make sense to: > >>> > >>> a) allow people to disable listening on UDP in addition to TCP > >> I see no reason whatsoever to turn off TCP listeners especially > >> since that is the protocol of choice... something we have > >> be spouting about for years... > >> > > > > There are reasons to be able to turn off TCP listeners: > > > > If you're running a NFSv4-only server, there's no reason to allow it to > > listen on TCP _or_ UDP sockets. I think that sort of environment is > > going to become more prevalent in the future, not less. > I ideally it would be best not to have mountd at all on NFSv4-only server. > Basically, have the kernel get its exports like it gets it ID mappings. > Until that day comes, which I hope fill be soon, the TCP listener > only effects v3 mounts and we definitely want people to use TCP > with v3. I'm not sure if we want to do that, but note one thing we'll need to do before then is solve the namespace problems. (We don't currently have a good way to run the usermode helper in the right container.) --b.