Hi Med, 

> On Jan 22, 2024, at 02:44, [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.


It does cover it with “validation constraints” and “deviations of observed 
behavior”. However, it might be good to explicitly cover “mandatory” since this 
indicates to return a data node rather than suppress data nodes not being 
returned due to validation. 


Thanks,
Acee




>  
> 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.

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

Reply via email to