Re: [netmod] Inventory YANG model (entity-MIB)

[Juergen Schoenwaelder <[e-mail]>]

On Sun, Mar 08, 2015 at 03:08:37PM -0400, Jeffrey Haas wrote:
> [speaking largely as a contributor and not i2rs-chair]
> 
> On Fri, Mar 06, 2015 at 12:05:36PM +0100, Juergen Schoenwaelder wrote:
> > My first question is (perhaps not surprising) whether inventory falls
> > into the I2RS charter, I2RS = interface to the routing system. That
> > said, RFC 6643 gives you a read-only translation. There are not many
> > read-write objects in the ENTITY-MIB so perhaps this is good enough
> > for now. I guess it would help what I2RS needs to know in order to
> > make the interface to the routing system work.
> 
> As discussed later in thread, having this work owned by netmod is fine with
> I2RS.
> 
> The structure of the generic topology draft is leading to interesting
> questions about how information present in that model can link to higher and
> lower layers.  As seen in the I2RS presentations at the most recent interim,
> this eventually leads to questions like "inventory".  I also raised the
> question about tunnels which will lead to other models as well.
> 
> The fact that the IETF already has good models for some of these things, the
> ENTITY-MIB as an example, is good.  However, simple conversion of MIBs to
> yang modules are likely to result in models that are good MIB replacements,
> but might not be well tailored to re-use elsewhere.  Since much of the
> motivation is for re-use, re-use is the discussion I would suggest is most
> important.
> 
> As an example, SNMP tables probably should be converted into yang groupings.
> There's also the matter of indexing of such conversions may not be fully
> appropriate for such re-use and alternate indexes may be helpful.

Nobody is insisting on an SNMP translation but whatever is done better
allows export via the ENTITY-MIB as well - things need to be aligned
at least. I note that many of the things you mention are not part of
draft-dong-i2rs-network-inventory-00.txt either.

> > PS: I personally would have preferred if generic topology and perhaps
> >     inventory would have split off into a short-lived targeted WG
> >     instead of doing all of this in I2RS but it seems leadership has
> >     already decided that I2RS is the home for all of this.
> 
> [speaking as one of the i2rs-chairs]
> 
> Topology was one of the use cases that was in-charter and we're not looking
> to significantly expand our charter work.  But one thing we've noted over
> the life of the group is that there has been a lot of push for micro-WG to
> be formed for various yang efforts.  I personally believe we're better off
> with some owning WG taking on the task but handling it within the context of
> a design team.  The overhead of a full WG is likely not merited.
> 
> Which WG the design team reports to is, of course, up for discussion.
>

What was in the original I2RS charter was routing topology export
(read-only). Going from there to a generic topology model (which
likely should not be limited to config false) is quite a step. I
personally find it sub-optimal to do the generic model in WG A and
several extensions of the generic model in WG B plus some more
extensions in WG C, most likely crossing IETF areas. The coordination
resulting from this will most likely slow things down.

/js

-- 
Juergen Schoenwaelder           Jacobs University Bremen gGmbH
Phone: [phone]         Campus Ring 1 | 28759 Bremen | Germany
Fax:   [phone]         <http://www.jacobs-university.de/>