Re: [Idr] Can one Destination Address appear in both Tunnel Encap Attribute and in MP_REACH_NLRI ?

Ondrej Zajicek <santiago@crfreenet.org> Thu, 17 October 2019 09:33 UTC

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Date: Thu, 17 Oct 2019 11:33:08 +0200
From: Ondrej Zajicek <santiago@crfreenet.org>
To: Robert Raszuk <robert@raszuk.net>
Cc: Srihari Sangli <ssangli@juniper.net>, "idr@ietf.org" <idr@ietf.org>, Linda Dunbar <linda.dunbar@futurewei.com>, Srihari Sangli <ssangli=40juniper.net@dmarc.ietf.org>, "draft-ietf-idr-tunnel-encaps@ietf.org" <draft-ietf-idr-tunnel-encaps@ietf.org>
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Subject: Re: [Idr] Can one Destination Address appear in both Tunnel Encap Attribute and in MP_REACH_NLRI ?
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On Thu, Oct 17, 2019 at 10:25:13AM +0200, Robert Raszuk wrote:
> Srihari,
> 
> Can you comment on the expected BGP next hop validation behaviour ?
> 
> Can you also comment on the next hop BGP is installing the prefixes to RIB
> with ?
> 
> Is tunnel endpoint now the NH BGP is asking RIB to track ?

My impression of the draft is that handling of BGP NH and address from
Tunnel Encap attribute is different. BGP NH is tracked in RIB and
recursivery resolved, could be used to daisy-chain encapsulation in RIB
(section 7). In contrast, the address from the Tunnel attribute is just
passed to FIB as encapsulation action argument.

But it is true that this part of the draft is a bit blurry and would
definitely need more clear wording.

-- 
Ondrej 'Santiago' Zajicek (email: santiago@crfreenet.org)