Hi Mahesh,

Please see inline.

Cheers,
Med

De : Mahesh Jethanandani <[email protected]>
Envoyé : lundi 22 janvier 2024 17:43
À : BOUCADAIR Mohamed INNOV/NET <[email protected]>
Cc : Acee Lindem <[email protected]>; YANG Doctors <[email protected]>; 
[email protected]; [email protected]
Objet : Re: [yang-doctors] [netmod] Operational State usage of YANG choices and 
constraints (fix draft address)

Hi Med,


On Jan 21, 2024, at 11:44 PM, 
[email protected]<mailto:[email protected]> wrote:

Hi Acee,

> I think these points are worth addressing in RFC8407 BIS.

We do already have the following in the bis, which I think covers your initial 
question about “mandatory true” data nodes for operational state”:

   Section 8.1 of [RFC7950] includes a provision for defining a
   constraint on state data and specifies that the constraint must be
   true in a valid state data.  However, Section 5.3 of [RFC8342]
   softens that behavior by allowing semantic constraints to be violated
   under some circumstances to help detecting anomalies.  Relaxing
   validation constraints on state data is meant to reveal deviations of
   the observed behavior vs. intended behavior of a managed entity and
   hopefully trigger corrective actions by a management system.  From
   that perspective, it is RECOMMENDED to avoid defining constraints on
   state data that would hinder the detection by a management system of
   abnormal behaviors of a managed entity.

[mj] When I read this, it tells me that it is ok to put constraints on state 
data.

[Med] The key part is the reco in the last sentence. I think we have a valid 
path here given what is in 8.1 of 7950 and the provisions in 5.3 of 8342.

What I am hearing on the mailing list, by Juergen and others, is questioning 
the use of constraints on state data. What I am interested in understanding is, 
would there be a problem in dropping/ignoring constraints on state data?

Thanks.



No?

Cheers,
Med

De : netmod <[email protected]<mailto:[email protected]>> De la 
part de Acee Lindem
Envoyé : vendredi 19 janvier 2024 18:47
À : Andy Bierman <[email protected]<mailto:[email protected]>>
Cc : Jürgen Schönwälder 
<[email protected]<mailto:[email protected]>>;
 YANG Doctors <[email protected]<mailto:[email protected]>>; 
[email protected]<mailto:[email protected]>; 
[email protected]<mailto:[email protected]>
Objet : Re: [netmod] [yang-doctors] Operational State usage of YANG choices and 
constraints (fix draft address)

Hi Andy,



On Jan 19, 2024, at 12:17, Andy Bierman 
<[email protected]<mailto:[email protected]>> wrote:



On Fri, Jan 19, 2024 at 9:02 AM Acee Lindem 
<[email protected]<mailto:[email protected]>> wrote:
Along the same lines, what is the sentiment for “mandatory true” data nodes for 
operational state (i.e., “config false” nodes)? Does this make sense to 
identify data nodes the must be returned if the parent node is returned?


What does "must be returned" mean?

Obviously, it does not mean returning the data even if the filters do not 
select that node. (I hope)
I used to think it meant conformance  (whether the server must implement or may 
implement).
I was told years ago that is not the case. Use if-feature for that. No 
if-feature == mandatory-to-implement.

If a client requests the parent subtree, then how would it know the difference 
between config=false
nodes that are not present vs. the server just decided not to return them (even 
though conformance
to the retrieval operation requires them)?

IMO the mandatory-stmt for config=false nodes does not make any sense at all.

I’m fine with that - we just need to make sure that this is reflected in our 
IETF models. I think these points are worth addressing in RFC8407 BIS.

Thanks,
Acee







Thanks
Acee

Andy

> On Dec 22, 2023, at 2:36 PM, Jürgen Schönwälder 
> <[email protected]<mailto:[email protected]>>
>  wrote:
>
> On Fri, Dec 22, 2023 at 07:22:55PM +0000, Kent Watsen wrote:
>> With limited experience wrt the impact on servers, as a client, it’s always 
>> best for the opstate data to be modeled as accurately as possible, for 
>> better processing and user experience.
>>
>
> What is accurate?
>
> I think the answer is "it depends". There are states that a model
> allows to represent and there are states it does not allow to
> represent. If a device ends up in a state that the model can't
> represent, then the device has a problem, From a debugging point of
> view, the worst is a device in a state that can't be represented
> propoerly reporting a valid state it is not in.
>
> So like everything else, it is a modeling decision, like picking types
> and everything else. I am not sure that 'as accurate as possible" is a
> helpful guideline; for operational state I prefer to see as much as
> possible the device's true state. (But even picking data types for
> leaves restricts what can be represented, so it is a judgement call.)
>
> /js
>
> --
> Jürgen Schönwälder              Constructor University Bremen gGmbH
> Phone: +49 421 200 3587         Campus Ring 1 | 28759 Bremen | Germany
> Fax:   +49 421 200 3103         <https://constructor.university/>

_______________________________________________
yang-doctors mailing list
[email protected]<mailto:[email protected]>
https://www.ietf.org/mailman/listinfo/yang-doctors

____________________________________________________________________________________________________________

Ce message et ses pieces jointes peuvent contenir des informations 
confidentielles ou privilegiees et ne doivent donc

pas etre diffuses, exploites ou copies sans autorisation. Si vous avez recu ce 
message par erreur, veuillez le signaler

a l'expediteur et le detruire ainsi que les pieces jointes. Les messages 
electroniques etant susceptibles d'alteration,

Orange decline toute responsabilite si ce message a ete altere, deforme ou 
falsifie. Merci.



This message and its attachments may contain confidential or privileged 
information that may be protected by law;

they should not be distributed, used or copied without authorisation.

If you have received this email in error, please notify the sender and delete 
this message and its attachments.

As emails may be altered, Orange is not liable for messages that have been 
modified, changed or falsified.

Thank you.
_______________________________________________
yang-doctors mailing list
[email protected]<mailto:[email protected]>
https://www.ietf.org/mailman/listinfo/yang-doctors


Mahesh Jethanandani
[email protected]<mailto:[email protected]>





____________________________________________________________________________________________________________
Ce message et ses pieces jointes peuvent contenir des informations 
confidentielles ou privilegiees et ne doivent donc
pas etre diffuses, exploites ou copies sans autorisation. Si vous avez recu ce 
message par erreur, veuillez le signaler
a l'expediteur et le detruire ainsi que les pieces jointes. Les messages 
electroniques etant susceptibles d'alteration,
Orange decline toute responsabilite si ce message a ete altere, deforme ou 
falsifie. Merci.

This message and its attachments may contain confidential or privileged 
information that may be protected by law;
they should not be distributed, used or copied without authorisation.
If you have received this email in error, please notify the sender and delete 
this message and its attachments.
As emails may be altered, Orange is not liable for messages that have been 
modified, changed or falsified.
Thank you.
_______________________________________________
netmod mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/netmod

Reply via email to