Re: [netmod] YANG next

Balázs Lengyel <balazs.lengyel@ericsson.com> Tue, 23 July 2019 16:22 UTC

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From: =?iso-8859-1?Q?Bal=E1zs_Lengyel?= <balazs.lengyel@ericsson.com>
To: Ladislav Lhotka <lhotka@nic.cz>, NETMOD WG <netmod@ietf.org>
Thread-Topic: [netmod] YANG next
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Date: Tue, 23 Jul 2019 16:22:30 +0000
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Archived-At: <https://mailarchive.ietf.org/arch/msg/netmod/Tez_6HQTxr0gwjTD5RyAWCXJsZc>
Subject: Re: [netmod] YANG next
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Hello,
I share your concerns. However I see some ways of mitigating the problem:
1) Maybe the extension based solution is better than many people would
believe. If we put new features (like status-information,
import-revision-or-derived, preliminary-status etc.) into extensions e.g.
Yang1-2:status-information older systems can just ignore them while never
systems would still be able to use them. This might not work for all new
functionality, but would definitely work for some.
2) Some yang-next ideas are really clarifications of yang 1.1 (e.g. Clarify
YANG "status" keyword usage (e.g., hierarchical)) so they will not disturb
current users.
Regards Balazs

-----Original Message-----
From: netmod <netmod-bounces@ietf.org> On Behalf Of Ladislav Lhotka
Sent: 2019. július 23., kedd 12:03
To: NETMOD WG <netmod@ietf.org>
Subject: [netmod] YANG next

Hi,

this morning I attended the side meeting "Next Step of IETF YANG". I was
somewhat misled into thinking that it would be about future evolution of
YANG the language, which was not the case at all. However, my personal
conclusion from the meeting is that it would be a total disaster to throw in
a new version of YANG within the next few years or so.

The operators and equipment vendors are busy putting together YANG modules
and tools, filling the gaps, coping with NMDA, schema mount, IETF versus
OpenConfig etc. A new YANG version (and modules written in it) would IMO be
extremely counter-productive at this rather turbulent stage.

So, if we want to continue the yang-next discussion, I think we first have
to figure out how to evolve YANG without making waves in the current YANG
pond and let the operators and vendors do their work, without which YANG can
never succeed.

Lada

--
Ladislav Lhotka
Head, CZ.NIC Labs
PGP Key ID: 0xB8F92B08A9F76C67

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