Re: [netmod] *one* week 2nd WG Last Call: draft-ietf-netmod-revised-datastores-07

Ladislav Lhotka <lhotka@nic.cz> wrote:
> Martin Bjorklund <mbj@tail-f.com> writes:
> 
> > Hi Andy,
> >
> > Andy Bierman <andy@yumaworks.com> wrote:
> >> Hi,
> >> 
> >> I have reviewed draft-07 and my previous comments about NMDA have been
> >> addressed.
> >> 
> >> This might be the most important sentence in the draft:
> >> 
> >> sec. 5.3
> >> 
> >>    The datastore schema for <operational> MUST be a superset of the
> >>    combined datastore schema used in all configuration datastores except
> >>    that YANG nodes supported in a configuration datastore MAY be omitted
> >>    from <operational> if a server is not able to accurately report them.
> >> 
> >> The MUST implies that there is no need to design a YANG library that can
> >> support
> >> an implementation that violates this MUST (i.e., 1 schema tree for the
> >> super-set)
> >> 
> >> The MAY is troublesome because it completely contradicts the conformance
> >> expressed
> >> in each YANG module supported by the server.  Any data node without any
> >> if-feature-stmts is mandatory to implement.
> >
> > This is required for transition purposes; a server that wants to
> > implement <operational> should not have to implement all modules at
> > once (as applied config).
> >
> >> What about config=false subtrees within a config=true subtree?
> >> Can they be omitted from <operational> as well, or does the draft just
> >> intend to
> >> omit the operational value of config=true nodes?  Should be specific.
> >
> > The text says "nodes supported in a configuration datastore MAY be
> > omitted from <operational>".  So it is implicit that it only applies
> > to config true nodes (since config false cannot be supported in a
> > config ds).  How about:
> >
> > OLD:
> >
> >     The datastore schema for <operational> MUST be a superset of the
> >     combined datastore schema used in all configuration datastores except
> >     that YANG nodes supported in a configuration datastore MAY be omitted
> >     from <operational> if a server is not able to accurately report them.
> >
> > NEW:
> >
> >     The datastore schema for <operational> MUST be a superset of the
> >     combined datastore schema used in all configuration datastores
> >     except that YANG "config true" nodes supported in a configuration
> 
> If this is about schema or data nodes, I suggest to state it
> explicitly:
> 
>     ... "config true" schema/data nodes ...

Yes, the new text uses "configuration data nodes".

> >     datastore MAY be omitted from <operational> if a server is not
> >     able to accurately report them.
> >
> >
> >> Perhaps this draft does not need the MAY half of the sentence at all.
> >> The YANG library can specify that it is for conformance-reporting, not
> >> conformance-defining.
> >
> > I think we should keep the MAY, since the YANG library has to be
> > designed to support this case.
> 
> Shouldn't the server add corresponding deviations to the schema for
> <operational> in this case?

We wanted to explicitly support the case that a server doesn't (yet)
implement a given module with config nodes in operational.  But maybe
we should design for the future and remove the MAY half of the
sentence, as suggested above, and let such servers use deviations in
this case.

/martin

> 
> Lada
> 
> >
> >
> > /martin
> >
> >
> >
> >
> >> 
> >> 
> >> 
> >> 
> >> Andy
> >> 
> >> 
> >> On Mon, Dec 4, 2017 at 6:35 AM, Lou Berger <lberger@labn.net> wrote:
> >> 
> >> > All,
> >> >
> >> > This starts a second working group last call on
> >> > draft-ietf-netmod-revised-datastores.
> >> >
> >> > As this is a 2nd LC that is focused on changes since the last LC, it
> >> > closes in *one* week. The working group last call ends on December 11.
> >> > Please send your comments to the netmod mailing list.
> >> >
> >> > At this point, we're most interested in verifying that previous comments
> >> > are addressed since the last call on the -04 rev of the draft was held.
> >> >
> >> > A summary of changes can be found at
> >> > https://mailarchive.ietf.org/arch/msg/netmod/DWtD12bGkBZabEygRfiwZfcnUU4
> >> >
> >> > A diff can be found at
> >> > https://tools.ietf.org/rfcdiff?difftype=--hwdiff&url1=draft-ietf-netmod-
> >> > revised-datastores-04.txt&url2=draft-ietf-netmod-revised-datastores-07.txt
> >> >
> >> > Comments along the of: I have reviewed this version of the document and it
> >> > addresses my previous comments would be particularly helpful.
> >> >
> >> > Thank you,
> >> > Netmod Chairs
> >> >
> >> > _______________________________________________
> >> > netmod mailing list
> >> > netmod@ietf.org
> >> > https://www.ietf.org/mailman/listinfo/netmod
> >> >
> >
> > _______________________________________________
> > netmod mailing list
> > netmod@ietf.org
> > https://www.ietf.org/mailman/listinfo/netmod
> 
> -- 
> Ladislav Lhotka
> Head, CZ.NIC Labs
> PGP Key ID: 0xB8F92B08A9F76C67
> 