Received-SPF: pass (google.com: domain of linux-nfs-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Wed, 23 Sep 2020 10:40:56 -0400
To:     Chris Hall <linux-nfs@gmch.uk>
Cc:     linux-nfs@vger.kernel.org
Subject: Re: mount.nfs4 and logging
Message-ID: <20200923144056.GB4691@fieldses.org>
References: <S1725851AbgIKKt5/20200911104957Z+185@vger.kernel.org>
 <a38a1249-c570-9069-a498-5e17d85a418a@gmch.uk>
 <f06f86ef-08bd-3974-3d92-1fbda700cc11@RedHat.com>
 <f7b9c8b4-29a6-2f28-b1d9-739c546fd557@gmch.uk>
 <20200919163353.GA15785@fieldses.org>
 <20200919164020.GB15785@fieldses.org>
 <12298172-f830-4f22-8612-dfbbc74b8a40@gmch.uk>
 <20200920193245.GC28449@fieldses.org>
 <eb64e66e-0328-f9e6-7511-1b73f67c49c1@gmch.uk>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <eb64e66e-0328-f9e6-7511-1b73f67c49c1@gmch.uk>
User-Agent: Mutt/1.5.21 (2010-09-15)
From:   bfields@fieldses.org (J. Bruce Fields)
Precedence: bulk

On Mon, Sep 21, 2020 at 03:40:01PM +0100, Chris Hall wrote:
> On 20/09/2020 20:32, J. Bruce Fields wrote:
> >On Sun, Sep 20, 2020 at 10:56:28AM +0100, Chris Hall wrote:
> ...
> >>Where nfsdcld, rpc.idmapd and rpc.mountd have indeed been started
> >>but are not bound to any ports.
> 
> >That looks good.  (And rpc.mountd does still serve a purpose in the
> >NFSv4 case, answering requests from the kernel for information related
> >to exported filesystems.)
> 
> >>But rpc.statd and rpcbind have also been started, and various ports
> >>have been opened, including port 111 which is bound to systemd.  Is
> >>there a way to inhibit that for nfs4 only ?
> 
> >Unlike rpc.mountd, there's no reason for those to be running at all.
> >You can mask thoe corresponding systemd units.
> 
> I tried masking all of: rpcbind.socket, rpcbind.service,
> statd.service and statd-notify.service.  systemctl start
> nfs-server.service (eventually) gives, according to the logging:
> 
>  nfs-mountd.service: start operation timed out. Terminating.
>  nfs-mountd.service: State 'stop-sigterm' timed out. Killing.
>  nfs-mountd.service: Killing process x (rpc.mountd) with signal SIGKILL.
>  nfs-mountd.service: Control process exited, code=killed, status=9/KILL

Huh, that suggests rpc.mountd is trying to contact rpcbind, but if
you've got v2/v3 turned off in the configuration files, it shouldn't be
trying to register anything.

Looking at the code....  I wonder if the problem is the unregistration
added by 849b7072a049 "mountd: Clear mountd registrations at start up"?

> If I unmask rpcbind.service, I can start nfs-server.  It no longer
> starts rpc.statd.  But I still have rpcbind running and port 111
> open.
> 
> >It'd be nice if there was a way to make that happen automatically if v2
> >and v3 are configured out in the configuration files, but I don't know
> >how to make that happen.
> 
> It would and me neither.

I suppose they could check the configuration and exit on startup if they
see they're not needed.  Will systemd notice they died and try to
restart them or something?

--b.