Re: [PATCH 1/2] nfs-service: Added the starting of gssproxy

[Simo Sorce <simo@redhat.com>]

On Mon, 22 Sep 2014 17:14:05 -0400
Steve Dickson <SteveD@redhat.com> wrote:

> 
> 
> On 09/22/2014 04:44 PM, J. Bruce Fields wrote:
> > On Mon, Sep 22, 2014 at 03:43:09PM -0400, Steve Dickson wrote:
> >>
> >>
> >> On 09/22/2014 03:26 PM, Simo Sorce wrote:
> >>> On Mon, 22 Sep 2014 15:20:07 -0400
> >>> Steve Dickson <steved@redhat.com> wrote:
> >>>
> >>>> Added the gssproxy.service to both the Wants= and
> >>>> Atfers= lines, before the rpc-svcgssd.service. There
> >>>> are  ConditionPathExists= lines in the rpc-svcgssd.service
> >>>> unit which will stop the rpc.svcgssd daemon from
> >>>> starting when the gssproxy daemon is already running.
> >>>>
> >>>> Signed-off-by: Steve Dickson <steved@redhat.com>
> >>>> ---
> >>>>  systemd/nfs-server.service | 5 +++--
> >>>>  1 file changed, 3 insertions(+), 2 deletions(-)
> >>>>
> >>>> diff --git a/systemd/nfs-server.service
> >>>> b/systemd/nfs-server.service index 2fa7387..c740fa2 100644
> >>>> --- a/systemd/nfs-server.service
> >>>> +++ b/systemd/nfs-server.service
> >>>> @@ -2,12 +2,13 @@
> >>>>  Description=NFS server and services
> >>>>  Requires= network.target proc-fs-nfsd.mount rpcbind.target
> >>>>  Requires= nfs-mountd.service
> >>>> -Wants=rpc-statd.service nfs-idmapd.service rpc-gssd.service
> >>>> rpc-svcgssd.service +Wants=rpc-statd.service nfs-idmapd.service 
> >>>> +Wants=rpc-gssd.service  
> >>>>  Wants=rpc-statd-notify.service
> >>>>  
> >>>>  After= network.target proc-fs-nfsd.mount rpcbind.target
> >>>> nfs-mountd.service After= nfs-idmapd.service rpc-statd.service
> >>>> -After= rpc-gssd.service rpc-svcgssd.service
> >>>> +After= rpc-gssd.service gssproxy.service rpc-svcgssd.service
> >>>>  Before= rpc-statd-notify.service
> >>>>  
> >>>>  Wants=nfs-config.service
> >>>
> >>> I think you really need to insure that the modules are loaded
> >>> before any of the server services are started, perhaps adding a
> >>> unit file that exec's modprobe and has "Before: gssproxy.service
> >>>  " in it ?
> >> I really don't think its needed... From my testing it appears 
> >> gssproxy is always being started and rpc.svcgssd is not... 
> > 
> > Huh.  Well rpc-svcgssd.service has var-lib-nfs-rpc_pipefs.mount as
> > both "Requires=" and "After=", so rpc-svcgssd.service will never run
> > without first running var-lib-nfs-rpc_pipefs.mount, which will load
> > sunrpc.  But I don't see where auth_rpcgss is getting loaded.  And I
> > don't see what ensures anything happening before gssproxy runs.
> It happens during the mount on the client and when the server
> is started. 
> 
> > 
> > We want to make sure your testing's not just getting lucky on the
> > startup order.
> The reason it working is because rpc.gssd is being started on the
> server these days for callbacks and the After= line in
> rpc-svcgssd.service is being executed before the ConditionPathExists
> which cause rpc.svcgssd not to start.

This guarantees ordering (to some degree) between rpc.gssd and
rpoc.svcgssd, but says nothing about gssproxy ...

> So when gssproxy.service does it's "Before=nfs-secure.service
> nfs-secure-server.service" line everything is loaded before gssproxy
> start... 
> 
> I'm think gssproxy.service just needs to the put the Wants and After=
> var-lib-nfs-rpc_pipefs.mount lines, instead of that Before line.. 

Maybe we should add "Before: gssproxy.service rpc-svcgssd.service"
to var-lib-nfs-rpc_pipefs.mount instead (and also drop any mention of
nfs services in gssproxy unit file so you have complete control of the
dependencies ?

> > 
> >> Plus, from my understanding...  loading module from a service 
> >> file is a big no no! People were having problems with
> >> way back when... 
> > 
> > Any pointers?  Google's not finding me anything.
> Search the the Fedora bz's when systemd first came out... 
> There were a number of "colorful" discussion on how things
> were so broken until systemd came along and saved humanity!  ;-) 

This doesn't help really, I see no reason why we could not have a pre
exec statement to modprobe rpc_authgss in a unit file (whether that is
var-lib-nfs-rpc_pipefs.mount or something else), to guarantee correct
ordering.

Simo.

-- 
Simo Sorce * Red Hat, Inc * New York