Re: [netmod] Datastore leaf for yang instance data

[Balázs Lengyel <[e-mail]>]

On 2018. 11. 23. 16:49, Juergen Schoenwaelder wrote:
> On Fri, Nov 23, 2018 at 01:21:23PM +0000, Balázs Lengyel wrote:
>>     BALAZS: "Instance data associated with a datastore" may mean many things,
>>     that's why this relatively loose term is used. It may mean:
>>
>>       * Data was read from that datastore
>>       * Data is intended to be fed into that datastore
>>       * Something else ???
>>
>>     This can be useful if data is read from a datastore, but in a number of
>>     cases it is not useful:
>>
>>       * Preloading configuration data: datastore may be running or candidate.
>>       * Preloading mixed config and state data: We do have state data that is
>>         very stable and thus it is documented as instance data, and the
>>         instance data file is actually used to feed the state data into the
>>         SW. So datastore is: running, candidate + operational if NMDA is
>>         supported or state datastore (whatever that is) if NMDA is not
>>         supported
>>
>>     regards Balazs
>>
> I do not buy this story. Your software needs to decide somehow what
> instance data means. A config true leaf in candidate means something
> different than the same config true leaf in running and this yet again
> means something different than the same config true leaf in operational.
>
> /js

BALAZS: As I understood the WG decided that this draft should only be 
about the format of the yang instance data. What the SW does with it is 
out of scope. So considerations whether instance data should be loaded 
into running or candidate or not at all, are outside the scope.

I want to provide a datastore indicator, but how that should be used 
(and thus what is exactly means) is out of scope.

Anyway in some cases it would be problematic to define a single 
datastore parameter. E.g. the draft allows the real world use case of 
putting config and state data in the same file. In this case state data 
is associated with operational while config data is with 
running/candidate. In the non-NMDA case I do not even know what the 
correct daatastore is for state data.

-- 
Balazs Lengyel                       Ericsson Hungary Ltd.
Senior Specialist
Mobile: [phone]              email: [e-mail]