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

["Susan Hares" <[e-mail]>]

Juergen:

<chair hat on> 
Thank you for your input on location of work.  I will discuss this with Alia
and Jeff this morning.  If you do have input where a yang module updating
the Entity-MIB might be worked on, please drop me a note. 
<chair hat off>

Jie Dong, I, and other members of the I2RS topology task simply want to get
the inventory information added to some yang model.  In our multiple vendor
(Cisco, Ericsson, Juniper, Huawei, packet-design),  many people felt it was
reasonable.  

As technical advisor, do you know if the Entity-MIB work scheduled for
upgrading to a yang module?  If not, is there a working group where we could
suggest an equivalent model. 
  
As to config true,  this Data model seems IMHO (jie may correct me) one of
the I2RS model that wants to have ephemeral state but also change things in
the data store.  

<chair hat on> 
I asked the design teams to focus on the functions they desired in the
datastore so that we could see more test cases.  I hope you as the I2RS
technical advisor will help us dive into protocol issues with specific
models. 
<chair hat off> 


 
-----Original Message-----
From: Juergen Schoenwaelder [mailto:[e-mail]] 
Sent: Friday, March 06, 2015 6:06 AM
To: Benoit Claise
Cc: NETMOD Working Group; [e-mail];
[e-mail]
Subject: Re: [netmod] Inventory YANG model (entity-MIB)

On Fri, Mar 06, 2015 at 11:48:02AM +0100, Benoit Claise wrote:
> Dear all,
> 
> The I2RS interim meeting yesterday focused on topology.
> Let me cut/paste a high level slide, with pointers to the relevant drafts.
> 
> 
> If interested, the meeting minutes are at 
> http://etherpad.tools.ietf.org:9000/p/i2rs-interim-march-5-2015-v-blue
> sheets
> 
> Part of the inventory draft
> (http://datatracker.ietf.org/doc/draft-dong-i2rs-network-inventory/)
> discussion, the overlap with the ENTITY-MIB RFC 6933 was discussed 
> (and RFC 7223 btw).
> 
> 
> The message was that I2RS should not re-invent something similar to 
> the ENTITY-MIB So, are you aware of any initiatives to "YANGify" the 
> ENTITY-MIB?
> It's true that there is a way to translate MIB into YANG with RFC 6643. 
> This could be a good start. However, I wonder if a hand-written YANG 
> model that closely follows the entPhysical would not be more beneficial.
> Is this something we should take on board in NETMOD?
> 
> What do you think?
> 
> Note: As commented by the I2RS people, indexing is appropriate in the 
> MIB module for its original purpose, but may not be for the topology.
> I'm not sure we want to change the indexing just for the topology, but 
> the integration within the topology draft should be thought of.
>

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.

Anyway, if YANG models overlapping the ENTITY-MIB are done, they they
should at least allow implementation of both in a predictable manner.
Looking at draft-dong-i2rs-network-inventory-00, it seems the whole
interface list is already covered by RFC 7223 and interfaces should be
references not repeated (this is what the ENTITY-MIB does). So what is
left is essentially a (not yet hierarchy) of 'cards' that seem to more
or less match the entPhysicalTable of the ENTITY-MIB (but then the
ENTITY-MIB has a more flexible model that distinguishes between
different kind of hardware components). I also notice that the model
in draft-dong-i2rs-network-inventory-00 is config true - so I am not
sure how this is supposed to use. Is the idea that this model is an
interface to an inventory database where I configure what I have
instead of a model sitting on a device where I can query what the
device actually has?

/js

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.

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