Re: [PATCH 1/2] rpc-svcgssd.service: removed a the start up triggers

[NeilBrown <neilb@suse.de>]

[-- Attachment #1: Type: text/plain, Size: 2463 bytes --]

On Wed, 19 Feb 2014 11:03:36 -0500 Simo Sorce <simo@redhat.com> wrote:

> On Wed, 2014-02-19 at 14:17 +1100, NeilBrown wrote:
> > On Tue, 18 Feb 2014 03:48:48 -0500 Steve Dickson <steved@redhat.com> wrote:
> > 
> > > The file /proc/net/rpc/use-gss-proxy exists whether
> > > gss-proxy is or is not installed. So is existence
> > > can not be used as start up trigger.
> > > 
> > > Signed-off-by: Steve Dickson <steved@redhat.com>
> > > ---
> > >  systemd/rpc-svcgssd.service | 1 -
> > >  1 file changed, 1 deletion(-)
> > > 
> > > diff --git a/systemd/rpc-svcgssd.service b/systemd/rpc-svcgssd.service
> > > index 6bd4588..8e10b98 100644
> > > --- a/systemd/rpc-svcgssd.service
> > > +++ b/systemd/rpc-svcgssd.service
> > > @@ -7,7 +7,6 @@ PartOf=nfs-utils.service
> > >  
> > >  After=gssproxy.service
> > >  ConditionPathExists=|!@localstatedir@/run/gssproxy.pid
> > > -ConditionPathExists=|!/proc/net/rpc/use-gss-proxy
> > >  ConditionPathExists=/etc/krb5.keytab
> > >  
> > >  [Service]
> > 
> > This is testing for non-existence, not existence.
> > 
> > We need rpc-svcgssd unless gssproxy can perform that task for us, in which
> > case we don't want rpc-svcgssd.
> > 
> > gssproxy can only perform the task for us if:
> >  1/ it is running (hence the test on the pid file)
> 
> could be stale

Agreed.  But it is the best we have.  Systemd doesn't support
   ConditionUnitActive
or similar.

> 
> >  2/ the kernel knows how to talk to it (hence the test on use-gss-proxy)
> 
> use-gss-proxy is always available whether gss-proxy is being used or not
> as it is the interface used by gss-proxy to tell the kernel it is in
> use.

It is not available in linux 3.9 or earlier.

> 
> > With you version, if gssproxy were running on a kernel which did not include
> > support for nfsd talking to gssproxy, then rpc-svcgssd would fail to start,
> > which isn't what we want.
> 
> True the right way to handle this would probably be to
> make /proc/net/rpc/use-gss-proxy readable and start rpc.svcgssd if the
> value is 0 ?

Pity systemd doesn't have

   ConditionPathIsFileContaining

Even udev has that!


> 
> > This may be an unusual configuration but unless it is an impossible
> > configuration I would rather the code remained as it was.
> > (This should work on *all* distros, not just sane distros).
> 
> I agree with the sentiment.

Thanks,

NeilBrown



> 
> Simo.
> 


[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 828 bytes --]