Re: I-D Action: draft-ietf-bfd-yang-06.txt

"Acee Lindem (acee)" <> Thu, 27 July 2017 19:40 UTC

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From: "Acee Lindem (acee)" <>
To: "Reshad Rahman (rrahman)" <>, Yingzhen Qu <>, Jeffrey Haas <>, "" <>
CC: "" <>, "" <>
Subject: Re: I-D Action: draft-ietf-bfd-yang-06.txt
Thread-Topic: I-D Action: draft-ietf-bfd-yang-06.txt
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Date: Thu, 27 Jul 2017 19:40:14 +0000
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Hi Reshad, 

On 7/27/17, 3:35 PM, "Reshad Rahman (rrahman)" <> wrote:

>Hi Acee,
>1) I’ll see if others chime in on this but I am fine with having the
>client grouping in ietf-bfd-types.yang.
>2) bfd-grouping-common-cfg-parms has much more than just the
>multiplier/timers that the IGPs need. It also has BFD specific stuff
>(demand-mode, BFD auth) which IMO has no business outside of BFD.


>bfd-grouping-base-cfg-parms has only the multiplier/timers.

Perhaps, the addition of multiplier/timers to bfd-grouping-base-cfg-parms
isn’t pushed to GitHub yet. This version
ypes.yang only has the enabled leaf.


>On 2017-07-27, 3:30 PM, "Acee Lindem (acee)" <> wrote:
>>Hi Reshad, 
>>On 7/27/17, 3:19 PM, "Reshad Rahman (rrahman)" <> wrote:
>>>Hi Acee,
>>>When we met we agreed to have a new model for clients. Afterwards I
>>>decided to create a new types module, and still went ahead with the
>>>clients module. I am fine with having everything in the types module (no
>>>client module).
>>Although I don’t feel that strongly - I just don’t see that putting the
>>client config params in wrappers provides any benefit. As for detriments,
>>it requires more one more local modules for validation and one more level
>>of indirection to see what we are really allowing to be configured.
>>>I am not sure I fully understand your comment/question on
>>>bfd-client-ext-cfg-parms/bfd-grouping-common-cfg-parms. The reason we
>>>2 groupings is that some protocols may decide to have just the enable
>>>and others may also want the multiplier/timer.
>>The bfd-client-ext-cfg-parms grouping should use
>>bfd-types:bfd-grouping-common-cfg-parms rather than
>>bfd-types:bfd-client-base-cfg-parms - no? This would be more obvious w/o
>>the client module.
>>>On 2017-07-27, 3:07 PM, "Acee Lindem (acee)" <> wrote:
>>>>Hi Reshad, 
>>>>Why do we need a new YANG model for clients? Why can’t they just use
>>>>ietf-bfd-types.yang? I’d like to avoid the unnecessary levels of
>>>>indirection. In fact, it looks wrong to me since the grouping
>>>>bfd-client-ext-cfg-parms uses the grouping bfd-grouping-base-cfg-parms
>>>>which only contains the enabled leaf. I believe you meant to use
>>>>bfd-grouping-common-cfg-parms in the other new model. However, I don’t
>>>>any reason why client shouldn’t use this directly.
>>>>On 7/25/17, 2:33 PM, "Reshad Rahman (rrahman)" <>
>>>>>Hi Yingzhen,
>>>>>The grouping is available @
>>>>>If you¹d like changes to the grouping, send me an email.
>>>>>On 2017-07-21, 12:22 PM, "Yingzhen Qu" <> wrote:
>>>>>>Hi Reshad,
>>>>>>Thanks for the summary.
>>>>>>Both ospf and isis models will make corresponding changes when the
>>>>>>BFD grouping is available.
>>>>>>-----Original Message-----
>>>>>>From: Reshad Rahman (rrahman) []
>>>>>>Sent: Thursday, July 20, 2017 7:19 AM
>>>>>>To: Jeffrey Haas <>rg>;
>>>>>>Subject: Re: I-D Action: draft-ietf-bfd-yang-06.txt
>>>>>>We (BFD and OSPF YANG authors) had a discussion yesterday.
>>>>>>The agreement is that since IGP peers are auto-discovered, we want to
>>>>>>back the basic BFD config (multiplier + intervals) in IGP via a
>>>>>>BFD will provide that grouping in a specific YANG module. IGP BFD
>>>>>>will be in a separate module (separate from the main IGP module).
>>>>>>On 2017-07-05, 12:21 PM, "Rtg-bfd on behalf of Jeffrey Haas"
>>>>>>< on behalf of> wrote:
>>>>>>>Thanks authors for the edits on the BFD yang module.  This gets us a
>>>>>>>significant step closer to alignment with the rest of IETF for
>>>>>>>I'd like to encourage the working group to provide feedback on this
>>>>>>>issue and also the changes in the module.
>>>>>>>As noted in another thread, we still have to figure out how to deal
>>>>>>>with accommodating interaction of the BFD yang module with client
>>>>>>>example, the IGPs.  In particular, how do you configure the
>>>>>>>of the BFD sessions that may be dynamically instantiated based on
>>>>>>>control protocol activity?
>>>>>>>-- Jeff
>>>>>>>On Fri, Jun 30, 2017 at 12:55:59PM -0700,
>>>>>>>> A New Internet-Draft is available from the on-line Internet-Drafts
>>>>>>>> This draft is a work item of the Bidirectional Forwarding
>>>>>>>>of the IETF.
>>>>>>>>         Title           : YANG Data Model for Bidirectional
>>>>>>>>Detection (BFD)
>>>>>>>>         Authors         : Reshad Rahman
>>>>>>>>                           Lianshu Zheng
>>>>>>>>                           Mahesh Jethanandani
>>>>>>>>                           Santosh Pallagatti
>>>>>>>>                           Greg Mirsky
>>>>>>>> 	Filename        : draft-ietf-bfd-yang-06.txt
>>>>>>>> 	Pages           : 59
>>>>>>>> 	Date            : 2017-06-30
>>>>>>>> Abstract:
>>>>>>>>    This document defines a YANG data model that can be used to
>>>>>>>>    and manage Bidirectional Forwarding Detection (BFD).
>>>>>>>> The IETF datatracker status page for this draft is:
>>>>>>>> There are also htmlized versions available at:
>>>>>>>> A diff from the previous version is available at:
>>>>>>>> Please note that it may take a couple of minutes from the time of
>>>>>>>>submission  until the htmlized version and diff are available at
>>>>>>>> Internet-Drafts are also available by anonymous FTP at: