Re: [RTG-DIR] Rtgdir last call review of draft-ietf-rtgwg-yang-rib-extend-16

[Acee Lindem <[e-mail]>]

Hi Jeffrey, 

> On May 9, 2023, at 17:15, Jeffrey (Zhaohui) Zhang <[e-mail]> wrote:
> 
> Hi Acee,
> 
> For argument sake (this is non-blocking), I don't see difference between static routes and protocol-learned routes. Why would protocol-learned routes need to have nexthop-specific backup while static routes don't?

The static route definition is read-write so this would need to be supported as a feature since I don’t know anyone who supports this. If someone really wants this, they can do it with a separate augmentation model. There are other static options that are more widely implemented that we haven’t included in the base model. 

I don’t see a requirement given that backup next-hops can be defined via higher preference. I know that you are arguing that this backup isn’t “next-hop specific”. However, if you have ECMP, normally an IGP would use the ECMP as a back up as well (though, I’m aware that options have been implemented to override this). 

Thanks,
Acee



> 
> Thanks.
> Jeffrey
> 
> -----Original Message-----
> From: Acee Lindem <[e-mail]>
> Sent: Thursday, May 4, 2023 10:51 AM
> To: Jeffrey (Zhaohui) Zhang <[e-mail]>
> Cc: Yingzhen Qu <[e-mail]>; Routing Directorate <[e-mail]>; [e-mail]; [e-mail]; [e-mail]
> Subject: Re: Rtgdir last call review of draft-ietf-rtgwg-yang-rib-extend-16
> 
> [External Email. Be cautious of content]
> 
> 
> Hi Jeffrey,
> 
> 
>> On May 1, 2023, at 5:05 PM, Jeffrey (Zhaohui) Zhang <[e-mail]> wrote:
>> 
>> Hi Yingzhen,
>> I can go with that if that’s what the authors/WG’s preference, but my preference would be to cover it in the base specification itself. What’s the harm?
>> Anyway, this is not a blocking comment.
> 
> The way the backup static route use case is handled is by configuring multiple next-hops with different preferences. This is one of the most useful  extensions provided by this augmentation.
> 
> Thanks,
> Acee
> 
> 
>> Thanks.
>> Jeffrey
>> From: Yingzhen Qu <[e-mail]>
>> Sent: Monday, May 1, 2023 5:01 PM
>> To: Jeffrey (Zhaohui) Zhang <[e-mail]>
>> Cc: [e-mail]; [e-mail];
>> [e-mail]; [e-mail]
>> Subject: Re: Rtgdir last call review of
>> draft-ietf-rtgwg-yang-rib-extend-16
>> [External Email. Be cautious of content]  Hi Jeffrey,  Considering
>> this is not commonly used, I'd suggest if someone really needs it they can do an easy augmentation using the grouping defined in this draft.
>> Thanks,
>> Yingzhen
>> On Mon, May 1, 2023 at 1:52 PM Jeffrey (Zhaohui) Zhang <[e-mail]> wrote:
>> Hi Yingzhen,
>> From: Yingzhen Qu <[e-mail]>
>> Sent: Monday, May 1, 2023 4:46 PM
>> To: Jeffrey (Zhaohui) Zhang <[e-mail]>
>> Cc: [e-mail]; [e-mail];
>> [e-mail]; [e-mail]
>> Subject: Re: Rtgdir last call review of
>> draft-ietf-rtgwg-yang-rib-extend-16
>> [External Email. Be cautious of content]  Hi Jeffrey,  Thanks for the
>> review, please see my answers below.
>> Thanks,
>> Yingzhen
>> On Mon, May 1, 2023 at 11:43 AM Zhaohui Zhang via Datatracker <[e-mail]> wrote:
>> Reviewer: Zhaohui Zhang
>> Review result: Has Issues
>> 
>> I have the following one nit comment and one question:
>> 
>>  augment "/rt:routing/rt:ribs/rt:rib/"
>>    + "rt:routes/rt:route/rt:next-hop/rt:next-hop-options/"
>>    + "rt:next-hop-list/rt:next-hop-list/rt:next-hop"
>>  {
>>    description
>>      "Augment the multiple next hops with repair path.";
>>    uses repair-path;
>>  }
>> 
>> The description is slightly misleading. It is to agument a single
>> next-hop in the next-hop-list, not "multiple next hops".
>> [Yingzhen] how about: "Augment the next-hop with a repair path."
>> Zzh> Good.
>> Shouldn't the repair path be applicable to static routes as well?
>> [Yingzhen]: Theoretically you can have a repair-path for a static route, but have you seen this in deployment?
>> Zzh> Whether anyone implemented/deployed it that way, I think it’s quite reasonable and desired to have it covered in the spec. For example, a static route could be using if1 by default but if2 as backup (in case if1 is down).
>> Zzh> Jeffrey
>> Juniper Business Use Only
>> 
>> Juniper Business Use Only
> 
> 
> 
> Juniper Business Use Only