Re: [netmod] 答复: FW: a question about ietf-hardware yang module

[Martin Bjorklund <[e-mail]>]

Juergen Schoenwaelder <[e-mail]> wrote:
> On Thu, Jun 27, 2019 at 10:04:50PM +0200, Martin Bjorklund wrote:
> > Juergen Schoenwaelder <[e-mail]> wrote:
> > > On Thu, Jun 27, 2019 at 09:52:56PM +0200, Martin Bjorklund wrote:
> > > > > Yes, good point, I think the phrase "by a different hardware
> > > > > component" should be removed. It seems last-change should change when
> > > > > I unplug a component and I plug it back shortly after, i.e., a
> > > > > component is replaced by itself. So we have:
> > > > > 
> > > > >         "The last time a new hardware component has been added to the
> > > > >          '/hardware/component' list, or a hardware component has been
> > > > >          removed from the '/hardware/component' list, or a hardware
> > > > >          component in the '/hardware/component' list has been
> > > > >          replaced."
> > > > 
> > > > I think that this is still not clear what it means that a component
> > > > has been replaced.  Do you mean "replaced by a different hardware
> > > > component"?
> > > > 
> > > > Otherwise (unplug then plug in the same component), the system either
> > > > detects the removal and thus updates last-change, or it doesn't detect
> > > > the quick removal/insertion, and then it can't do anything.  Thus, I
> > > > don't think this case needs special treatment, and the text could be
> > > > just:
> > > > 
> > > >          "The last time a new hardware component has been added to the
> > > >           '/hardware/component' list, or a hardware component has been
> > > >           removed from the '/hardware/component' list."
> > > >
> > > 
> > > The question is whether every implementor will figure out that if the
> > > component found in some slot x-y-z is different from what is expected
> > > to be in slot x-y-z, this must be seen as a remove + add combination.
> > > If we include 'replace', then it may be clearer that even in the case
> > > where what is in slot x-y-z has changed, the last-change must be
> > > updated. (That is, the list element with the same name still exists
> > > but it is different from what was there before with the same name.)
> > 
> > But then we're back to where we started - what exactly does "different
> > from what was there before" mean?  Presumably that some leaf's value
> > is different...?
> >
> 
> Go back some emails, I have removed the 'different' phrase.

Perhaps we can say:

       [...] or a hardware
       component in the '/hardware/component' list has been
       replaced with a new hardware component with the same
       name.


/martin