Hi Rob,

> - In terms of properties that cannot be changed once written, I would rather 
> see this issue framed more in the direction of it just being extra 
> documentation written in a machine-readable way.  Specifically, using the 
> annotation to give an indication that servers MAY reject requests to 
> create/delete, or change, the configuration, but not requiring that they do 
> so.  I.e., at the data model level, I don't think that we should preclude 
> servers being able to handle this is in a more client friendly way (e.g., by 
> breaking a single client transaction up into multiple internal transactional 
> changes where needed).

I agree that the document does not make it clear enough, but this is already 
the case.   As I said at the end of this document's presentation on Friday's 
NETMOD, session, this document has no runtime-impact on servers (other than 
them needing to return annotated YANG and/or metadata).  There is also no 
runtime-impact on clients, as they as free to ignore all the annotations and 
metadata.   All this document does is define a mechanism for servers to 
describe the behavior they already implement.   The text in the document is 
confusing because the normative statements make it sound like the server needs 
to implement behavior to reject certain updates *because annotations/metadata 
said so*, but actually it's the other way around, as the server was already 
implemented to reject the changes.

1st paragraph in the Introduction:

This document defines a way to formally document as a YANG extension or YANG 
metadata an existing model handling behavior that is already allowed in YANG 
and which has been used by multiple standard organizations and vendors. It is 
the aim to create one single standard solution for documenting modification 
restrictions on data declared as configuration, instead of the multiple 
existing vendor and organization specific solutions. See Appendix B 
<https://datatracker.ietf.org/doc/html/draft-ma-netmod-immutable-flag#Existing_implementations>
 for existing implementations.ΒΆ 
<https://datatracker.ietf.org/doc/html/draft-ma-netmod-immutable-flag#section-1-1>




> - For any immutable related metadata annotations, I think that this 
> additional metadata should only be returned to clients when explicit 
> requested via a separate RPC parameter, and I think that the draft needs to 
> add text for protocol capabilities used to indicate whether this new option 
> is supported (e.g., along the lines of RFC 6243, with-defaults).

Somewhat agree (Principle of Least Astonishment), though it's neither illegal, 
would cause client problems, or cause excessive network utilization (unlike 
with-defaults).

K.



_______________________________________________
netmod mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/netmod

Reply via email to