Subject: Re: [netmod] I-D Action: draft-ietf-netmod-ip-cfg-13.txt

From: "Yi Yang (yiya)" <[email-masked]>
Date: Fri, 7 Mar 2014 21:58:04 +0000

In the context of IP, each interface is associated with one and only one
VRF -- which is not reflected in the current data model.

Yi

On 2/13/14 1:33 PM, "[email-masked]" <[email-masked]>
wrote:

>
>A New Internet-Draft is available from the on-line Internet-Drafts
>directories.
> This draft is a work item of the NETCONF Data Modeling Language Working
>Group of the IETF.
>
>        Title           : A YANG Data Model for IP Management
>        Author          : Martin Bjorklund
>	Filename        : draft-ietf-netmod-ip-cfg-13.txt
>	Pages           : 32
>	Date            : 2014-02-13
>
>Abstract:
>   This document defines a YANG data model for management of IP
>   implementations.  The data model includes configuration data and
>   state data.
>
>
>The IETF datatracker status page for this draft is:
>https://datatracker.ietf.org/doc/draft-ietf-netmod-ip-cfg/
>
>There's also a htmlized version available at:
>http://tools.ietf.org/html/draft-ietf-netmod-ip-cfg-13
>
>A diff from the previous version is available at:
>http://www.ietf.org/rfcdiff?url2=draft-ietf-netmod-ip-cfg-13
>
>
>Please note that it may take a couple of minutes from the time of
>submission
>until the htmlized version and diff are available at tools.ietf.org.
>
>Internet-Drafts are also available by anonymous FTP at:
>ftp://ftp.ietf.org/internet-drafts/
>
>_______________________________________________
>netmod mailing list
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>https://www.ietf.org/mailman/listinfo/netmod

---

From: Martin Bjorklund <[email-masked]>
Date: Fri, 07 Mar 2014 23:11:52 +0100 (CET)

> VRF -- which is not reflected in the current data model.

A VRF can be represented as a routing-instance, as defined in the
routing draft.  Such a routing-instance will have interfaces
associated to it.

See also the thread
http://www.ietf.org/mail-archive/web/netmod/current/msg09253.html

/martin

---

From: "Yi Yang (yiya)" <[email-masked]>
Date: Fri, 7 Mar 2014 22:17:43 +0000

Hi Martin,

Yes, a routing instance is associated with a VRF, but routing table and
interface should also be associated with VRF as well. This is like address
family, which should be referred in multiple data models. Actually, I'd
think the VRF/address family are just like glue, which help build the
association between routing tables, routing instances, and interfaces and
etc.

Yi

---

From: Ladislav Lhotka <[email-masked]>
Date: Fri, 7 Mar 2014 23:40:19 +0100

> interface should also be associated with VRF as well. This is like address

Each routing-instance has its own list of interfaces, and RIBs can be also made specific for a routing-instance. The draft explicitly envisions such restrictions:

   RIBs are global, which means that a RIB may be used by any or all
   routing instances.  However, an implementation MAY specify rules and
   restrictions for sharing RIBs among routing instances.

> association between routing tables, routing instances, and interfaces and

I don’t think though that VRFs are so ubiquitous to warrant their direct inclusion in the core routing data model. A separate module seems more appropriate.

Lada

--
Ladislav Lhotka, CZ.NIC Labs
PGP Key ID: E74E8C0C

---

From: "Yi Yang (yiya)" <[email-masked]>
Date: Fri, 7 Mar 2014 22:50:04 +0000

Hi Ladislav,

On 3/7/14 10:40 PM, "Ladislav Lhotka" <[email-masked]> wrote:

>Each routing-instance has its own list of interfaces, and RIBs can be
>also made specific for a routing-instance. The draft explicitly envisions
>such restrictions:
>
>   routing instances.

[yi]: A routing table can be associated with multiple routing instances,
but should be associated with only one VRF.

> However, an implementation MAY specify rules and
>I don¹t think though that VRFs are so ubiquitous to warrant their direct
>inclusion in the core routing data model. A separate module seems more
>appropriate.

[yi]: A vrf can be associated with multiple routing tables, so yes, a
separated data model for vrf is required. But in the DM for routing table,
we need a reference to the vrf.

Yi

---

From: Ladislav Lhotka <[email-masked]>
Date: Sat, 8 Mar 2014 08:51:55 +0100

> but should be associated with only one VRF.

Then you should define precise semantics of the routing instance and VRF (instance). I assume both concepts can be modelled as different types of “routing-instance” in the existing data model.

I actually suspect the semantics are vendor-specific.

> we need a reference to the vrf.

Right, so the VRF module is free to augment “rib" with a new parameter (or more of them) that establishes this relationship. The advantage of this approach is that implementations not supporting the VRF module won’t have the new parameter in their data model.

Lada

---

From: Juergen Schoenwaelder <[email-masked]>
Date: Sat, 8 Mar 2014 09:09:08 +0100

> we need a reference to the vrf.

Can you make a concrete proposal what you think is missing? Note that
the routing model passed WG last call and unless there is a major bug
I prefer to move this document forward as is. So please come up with a
concrete detailed proposal so that we can decide whether we have a bug
or not.

/js

-- 
Juergen Schoenwaelder           Jacobs University Bremen gGmbH
Phone: +49 421 200 3587         Campus Ring 1, 28759 Bremen, Germany
Fax:   +49 421 200 3103         <http://www.jacobs-university.de/>

---

From: Benoit Claise <[email-masked]>
Date: Fri, 21 Mar 2014 11:09:59 +0100

Dear all,

I take as granted that this issue is closed.
If this is not the case, quickly let me know as this draft is on the 
IESG telechat next Thursday.

Regards, Benoit