Re: [Idr] Debugging accepted routes from BGP speakers

Jeffrey Haas <jhaas@pfrc.org> Tue, 03 December 2019 14:51 UTC

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Date: Tue, 3 Dec 2019 09:55:56 -0500
From: Jeffrey Haas <jhaas@pfrc.org>
To: Jared Mauch <jared@puck.nether.net>
Cc: Robert Raszuk <robert@raszuk.net>, IDR <idr@ietf.org>
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Subject: Re: [Idr] Debugging accepted routes from BGP speakers
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[Answering a point elsewhere in thread.]

On Mon, Nov 18, 2019 at 05:47:35PM +0800, Jared Mauch wrote:
> There are varying desires from operators. It may be as simple as a count to the list of accepted or rejected NLRI. 
> 
> If you look at the text the desire is to know is this path eligible for selection. That is accepted. 

The lack of consistent proxy loop detection across implementations will make
this messy.  If downstream router will consider route R a loop, but upstream
sent it, you now have a discrepancy that will show up in a mechanism like
this.

What do you want the behavior to be?

Add-paths means that you'll send R1, R2, R3 all with the same destination.
Are you really happy getting back R1, R2, R3 with the same path id as
confirmation that the route is eligible?

-- Jeff