Here is what RFC 7950 says: 7.5.4.1. The "error-message" Statement
The "error-message" statement, which is optional, takes a string as an argument. If the constraint evaluates to "false", the string is passed as <error-message> in the <rpc-error> in NETCONF. Since state data is not (directly) modified by processing RPCs, which <rpc-error> would carry the <error-message>? If the answer is 'none', then why define an <error-message> for state data? My take has always been that operational state data should report as much as possible the true state of the device - even if the current state violates certain constraints. The entity to check constraints would be a managing system, not the managed system. That said, the wording in section 7.5.4.1 indicates that the designers had servers processing RPCs in mind. /js On Tue, Oct 31, 2023 at 10:40:15AM +0000, mohamed.boucad...@orange.com wrote: > Hi all, > > In the context of https://datatracker.ietf.org/doc/draft-ietf-pce-pcep-yang/, > Dhruv has received in the past a comment about the use of "must + > error-message" for "config false" data nodes. He reported that comment at > https://mailarchive.ietf.org/arch/msg/yang-doctors/gWnXnyNHPVv_nZB1PQjThAwP1JY/, > but without any follow-up. > > rfc7950#section-8.1 includes a provision for the use of "must" for state > data, but silent about the use of error-message. Some guidance for authors > may be useful here. > > The following options are being considered: > > (1) Remove both must and error-message for config false data nodes > (2) Remove error-message but keep the must > (3) keep both > > I think that (3) is OK as this is a formal way to detect anomalies in state > data, but I'm open to hear what the WG thinks. > > Opinions whether we need to include a mention about this in > draft-ietf-netmod-rfc8407bis are welcome. > > Thank you. > > Cheers, > Med > > ____________________________________________________________________________________________________________ > 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 > netmod@ietf.org > https://www.ietf.org/mailman/listinfo/netmod -- 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/> _______________________________________________ netmod mailing list netmod@ietf.org https://www.ietf.org/mailman/listinfo/netmod