Re: [Idr] new thread regarding capabilities handling

Robert Raszuk <> Fri, 28 April 2017 06:32 UTC

Return-Path: <>
Received: from localhost (localhost []) by (Postfix) with ESMTP id E61EB128B8D for <>; Thu, 27 Apr 2017 23:32:15 -0700 (PDT)
X-Virus-Scanned: amavisd-new at
X-Spam-Flag: NO
X-Spam-Score: -2.399
X-Spam-Status: No, score=-2.399 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, FREEMAIL_FORGED_FROMDOMAIN=0.199, FREEMAIL_FROM=0.001, HEADER_FROM_DIFFERENT_DOMAINS=0.001, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_LOW=-0.7, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: (amavisd-new); dkim=pass (2048-bit key)
Received: from ([]) by localhost ( []) (amavisd-new, port 10024) with ESMTP id r_AkRB0KcSD3 for <>; Thu, 27 Apr 2017 23:32:14 -0700 (PDT)
Received: from ( [IPv6:2607:f8b0:4001:c0b::232]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by (Postfix) with ESMTPS id 6C2301270A0 for <>; Thu, 27 Apr 2017 23:29:39 -0700 (PDT)
Received: by with SMTP id g66so30793886ite.1 for <>; Thu, 27 Apr 2017 23:29:39 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;; s=20161025; h=mime-version:sender:in-reply-to:references:from:date:message-id :subject:to:cc; bh=yQW3+zY+gAQ6A1Zo9cpZiW52DBsUqBPWNbUmF7O+fKs=; b=ZkiNym8mN2na0r/VxmxGhkUWtojN5nELrnfhZdoYBPDT5BW7qwwr/RqRBvm3bxTmoD 6rCPhzmgMmqnkBCY7vzP8PaHA+5LckrWVzFxniD/EMDVaP3ejZ2BnRWLGgO5/iEx5GF/ miJd8Wn8+qQ5euADQEVvxL+8Ax7zaCdqrVFGeWWoV57ZmL/V+zhGhMd3TgnpoVBt5/gT JvWDDRaNMCtYu92yWfN2dc+o2htDUOoIfealvRBvrRFLDMNucBTfmbs0705SvijFDXxJ swikTgW3/LqPCACZ+2VP3Ja6c6sWLRKMK6PaZp579O6n1WWtoA/d1HLrmqO97eaeTn5O 11+Q==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;; s=20161025; h=x-gm-message-state:mime-version:sender:in-reply-to:references:from :date:message-id:subject:to:cc; bh=yQW3+zY+gAQ6A1Zo9cpZiW52DBsUqBPWNbUmF7O+fKs=; b=jrlzgX3dLmmNDmFsKqabYxVrA0eChjAkQ8fFvk8v7ViNyXBG7619p7+VpcsGYj+eui FnOD2f+WZRzlyaBoHtF5FEqdtskAg4Essum3Z8KQNrFMUGGjwZS/bLmBt8ZlBP4pv/5f zgnexB6NQs3rdCfnb8KOsijE4soqH7uY2krVaKINj57mMinvz+LFclJ4EM0EgwPeIE1H /lHlJo/+dONL7Ebo3Cj/JQUvektf64KqDB2DWKH02HjieSjT1kbGfXyNBqlwRg2S11Jt D0ObFK3eCeEwprB1bJv5DOAjTZtKAkjHK0ZUwLJ5Tw1B7gFFu6bUSyztLS2lL21Gc379 mc8A==
X-Gm-Message-State: AN3rC/7yGPiiuPzu2oxMBsA5zrPsAEdolh582mQvHhZjlep1w7LLtU3H 56KXK1QIdIyvB2rXoVDpdjVeqQuufw==
X-Received: by with SMTP id d193mr7344644ith.18.1493360978812; Thu, 27 Apr 2017 23:29:38 -0700 (PDT)
MIME-Version: 1.0
Received: by with HTTP; Thu, 27 Apr 2017 23:29:37 -0700 (PDT)
Received: by with HTTP; Thu, 27 Apr 2017 23:29:37 -0700 (PDT)
In-Reply-To: <>
References: <> <> <> <> <> <>
From: Robert Raszuk <>
Date: Fri, 28 Apr 2017 02:29:37 -0400
X-Google-Sender-Auth: 0B3AvITrh7Llg9w4qhfI89FhQsI
Message-ID: <>
To: Mikael Abrahamsson <>
Cc: idr wg <>, Enke Chen <>
Content-Type: multipart/alternative; boundary=94eb2c113198a9e751054e343250
Archived-At: <>
Subject: Re: [Idr] new thread regarding capabilities handling
X-Mailman-Version: 2.1.22
Precedence: list
List-Id: Inter-Domain Routing <>
List-Unsubscribe: <>, <>
List-Archive: <>
List-Post: <>
List-Help: <>
List-Subscribe: <>, <>
X-List-Received-Date: Fri, 28 Apr 2017 06:32:16 -0000

Hi Mikael,


For the duration of gr timer you continue to forward till your bgp session
restarts and finishes sending you routes with end-of-rib marker.

You also do not propagate neither new best paths nor withdraws to your
other peers during this restart limiting amount of bgp churn.

Then you compare "stale" routes with fresh ones and adjust the delta both
within your box and to peers.

Just try it out ;)


On Apr 28, 2017 01:11, "Mikael Abrahamsson" <> wrote:

On Thu, 27 Apr 2017, Enke Chen wrote:

If there is sufficient interest, we can limit the capability to just
> AFI/SAFI without much work.  With GR though the interest seems to have
> dropped.

If someone had asked me 2 days ago "If you have GR enabled on a BGP session
and add an address family to that session, will this affect forwarding when
the session restarts" I would have said "YES!"

But from what I'm reading here, I would have been wrong? The session would
go down but RIB/FIB would be untouched because GR?

Mikael Abrahamsson    email:

Idr mailing list