Warren Kumari's Discuss on draft-ietf-bfd-yang-16: (with DISCUSS and COMMENT)

[Warren Kumari <[e-mail]>]

Warren Kumari has entered the following ballot position for
draft-ietf-bfd-yang-16: Discuss

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DISCUSS:
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Don't panic, this should be an easy DISCUSS to clear, but I think it important
for interoperability.

In multiple places, you have:
             +--ro number-of-sessions?
             +--ro number-of-sessions-up?
             +--ro number-of-sessions-down?
             +--ro number-of-sessions-admin-down?

I'm a little confused by the meaning of the counters, and didn't see them
clearly defined anywhere. Apologies if I missed it...

Are "number-of-sessions-admin-down" included in "number-of-sessions-down"?
Is 'number-of-sessions' always equal to 'number-of-sessions-up' +
'number-of-sessions-down', or is it always equal to 'number-of-sessions-up' +
'number-of-sessions-down' + 'number-of-sessions-admin-down', or are there other
cases?

E.g: I have created 10 sessions (because I have 10 interfaces). 5 of them are
down because there is no peer, 3 of them I've configured to be down (admin
down), and so 2 of them are up.

What should be in each of:
number-of-sessions?
number-of-sessions-up?
number-of-sessions-down?
number-of-sessions-admin-down?


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COMMENT:
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Thank you.

I also had a few minor nits:
Nits:
Section 1:
"The YANG modules in this document conform to the Network Management Datastore
Architecture (NMDA) Network Management Datastore Architecture [RFC8342]. " The
Department of Redundancy Department called and wants some of their words back
please :-)

Section 2:
"Since BFD is used for liveliness detection of various forwarding
   paths, there is no uniform key to identify a BFD session.  So the BFD
   data model is split in multiple YANG modules where each module
   corresponds to one type of forwarding path."
I think this would be more readable as:
"... to identify a BFD session, and so the BFD..."  (hey, I said it was a nit)