Re: [Idr] Bug in RFC 7911 (add-paths) and tie-breaking

Robert Raszuk <robert@raszuk.net> Fri, 25 June 2021 15:39 UTC

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From: Robert Raszuk <robert@raszuk.net>
Date: Fri, 25 Jun 2021 17:39:40 +0200
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To: Bruno Decraene <bruno.decraene@orange.com>
Cc: Claudio Jeker <cjeker@diehard.n-r-g.com>, John Scudder <jgs=40juniper.net@dmarc.ietf.org>, "idr@ietf. org" <idr@ietf.org>, "dwalton76@gmail.com" <dwalton76@gmail.com>
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Subject: Re: [Idr] Bug in RFC 7911 (add-paths) and tie-breaking
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Bruno,

Don't agree. If a BGP speaker spends two paths with path_id they will be
> identical on both RRs.
>
>
>
> [Bruno] You are assuming that your two “diverses RR” learn the paths from
> the same (set of) peers. I agree that this is typical, but this is not
> guaranteed. If not, the path-id would not be comparable.
>

If they are from different peers there is no problem to start with as best
path already picks path from lowest neighbor address.

Thx,
R.