Subject: Genart last call review of draft-ietf-netmod-schema-mount-10

From: Joel Halpern <[email-masked]>
Date: Thu, 28 Jun 2018 12:16:13 -0700

Reviewer: Joel Halpern
Review result: Almost Ready

I am the assigned Gen-ART reviewer for this draft. The General Area
Review Team (Gen-ART) reviews all IETF documents being processed
by the IESG for the IETF Chair.  Please treat these comments just
like any other last call comments.

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Document: draft-ietf-netmod-schema-mount-10
Reviewer: Joel Halpern
Review Date: 2018-06-28
IETF LC End Date: 2018-06-29
IESG Telechat date: Not scheduled for a telechat

Summary: This document is almost ready for publication as a Proposed Standards.
    I believe that the working group has gotten too close to the work, and
    failed to notice that important explanations that they understand do not
    actually appear in the document.

Major issues:
     There is no explanation in the document as to who controls mounting and
     how it is specified.  From this, I infer that the intention is that the
     server knows what is to be mounted at specific mount points, and does so. 
      The Client does not tell the server to mount specific schemas in specific
     places.  Ok.  Say so.  And explain that the server knows this by means
     external to the YANG modules.  The text explicitly states that the case
     where the mount point definition selects the data model to be mounted is
     NOT supported by this document.

    There is some ambiguity, quite possibly only in this reader, as to what a
    client finds when it does a NETCONF Get at or below the mount point.  I had
    assumed originally that it would find structure defined by the schema that
    is mounted there, as defined by the schema-mount container.  However, the
    Schema-mount definition itself states that what is found at the mount point
    is an instance of YANG library.   Given that this lefft me completely
    confused, please add some explanatory text?

Minor issues:
    N/A

Nits/editorial comments:
    The introduction, in its third paragraph refers to the "source or target
    YANG module" seeming to use both the term source and the term target to
    refer to the module with the uses or augments statement.  Even if other
    YANG documents use both terms, this is a confusing construction.

---

From: Martin Bjorklund <[email-masked]>
Date: Fri, 29 Jun 2018 11:53:26 +0200 (CEST)

Hi,

Thank you for your review!  Comments inline.

>      NOT supported by this document.

The document has the following text, which was supposed to cover this
case:

   Schema mount applies to the data model, and specifically does not
   assume anything about the source of instance data for the mounted
   schemas.  It may be implemented using the same instrumentation as the
   rest of the system, or it may be implemented by querying some other
   system.  Future specifications may define mechanisms to control or
   monitor the implementation of specific mount points.

But howabout we add a new paragraph after this:

   How and when specific mount points are instantiated by the server
   is out of scope for this document.  Such mechanisms may be defined
   in future specifications.

>     is mounted there, as defined by the schema-mount container.

This is correct.

>     However, the
>     is an instance of YANG library.

Hmm, do you mean the text in the YANG module:

               "This node indicates that the server has mounted
                'ietf-yang-library' at the mount point, and its
                instantiation provides the information about the mounted
                schema.

If so, maybe we can clarify by saying

               "This node indicates that the server has mounted
                at least the module 'ietf-yang-library' at the mount
                point, and its
                instantiation provides the information about the mounted
                schema.

> Given that this lefft me completely

How about:

OLD:

   With both mechanisms, the source or target YANG module explicitly
   defines the exact location in the schema tree where the new nodes are
   placed.

NEW:

   With both mechanisms, the YANG module with the "uses" or "augemnt"
   statement explicitly defines the exact location in the schema tree
   where the new nodes are placed.

/martin

---

From: "jmh.direct" <[email-masked]>
Date: Fri, 29 Jun 2018 09:41:15 -0400

Thank you.  Those changes will do the trick.  I realize they are small.  They fix a lot of confusion.
Yours,Joel
PS:  While I think the absence of information on how the server knows / decides what to mount where is unfortunate, I understand that to be the WG agreement and therefore am not objecting to progressing the document.

Sent via the Samsung Galaxy S® 6, an AT&T 4G LTE smartphone
-------- Original message --------From: Martin Bjorklund <[email-masked]> Date: 6/29/18  05:53  (GMT-05:00) To: [email-masked] Cc: [email-masked], [email-masked], [email-masked], [email-masked] Subject: Re: Genart last call review of draft-ietf-netmod-schema-mount-10 
Hi,

This is correct.

How about:

OLD:

NEW:

/martin