Re: [Idr] Question about BGP mandatory attribute missing behavior

Ajay L <ajayl.bro@gmail.com> Fri, 29 April 2016 20:08 UTC

Return-Path: <ajayl.bro@gmail.com>
X-Original-To: idr@ietfa.amsl.com
Delivered-To: idr@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id DDFE412B03B for <idr@ietfa.amsl.com>; Fri, 29 Apr 2016 13:08:25 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.699
X-Spam-Level:
X-Spam-Status: No, score=-2.699 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, FREEMAIL_FROM=0.001, HTML_MESSAGE=0.001, RCVD_IN_DNSWL_LOW=-0.7, SPF_PASS=-0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=gmail.com
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Dsu1iZgZ7nyh for <idr@ietfa.amsl.com>; Fri, 29 Apr 2016 13:08:24 -0700 (PDT)
Received: from mail-oi0-x233.google.com (mail-oi0-x233.google.com [IPv6:2607:f8b0:4003:c06::233]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id CF9F212B067 for <idr@ietf.org>; Fri, 29 Apr 2016 13:08:23 -0700 (PDT)
Received: by mail-oi0-x233.google.com with SMTP id x19so130847583oix.2 for <idr@ietf.org>; Fri, 29 Apr 2016 13:08:23 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to; bh=inirEwiaGvDzdvUYLHtvMc3CG7k5H9DdR+QPYU43RgI=; b=e6/2L5vJdKygMuM6/Y1FqBLWJ7SNnrylbC/GPZcgy2EYCNu801SYprMxvHVfRIwYwG 5K3XelkzFQ3ZNKdb1JqoDKjWSea4oz+2qyNjILiWMg4fDeYHvhFwaRnFwVCMuigHz2XK /RUruY6I59uB0tfn3bZUltTxj6G61ZYI4rIFufKZK8rqIQVP8LuTchtFWkZR6fCqx899 QNuEI2WAGGkng3cRCCHTbtRVQWpO7QASdad3fT0rKQ7ZFRQaI1VENbRZAIF5He0qj7pb OKamOg0J7Yyf3QYmcthA1JKAff6ytWSLlaxBIYjVQyBTAcjqVpz4h8MKi0qMgSQAwL72 NWpg==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to; bh=inirEwiaGvDzdvUYLHtvMc3CG7k5H9DdR+QPYU43RgI=; b=WOEN+bz2dR2azBudkQLGvckpFuuUqACNRHIcdctjQ+E4UzebfoY+3lLM3LGuAySI3e wN5DShz40t+KPZ+JdhJcF5FozLi5qH7S70CbVh2u+dDwQJysbi72kvwr2SzaLqUg69sx xwVJf5iwogfgFvyP0ZM/APNsJc3xdVqHHyYhoFceQLkPLNnuNtWqr3eEScXDuaA/2K2w m3SBsTVaYpDpDW11nNSzHI2QPujHsi2dYD5wDWcitffaJl5mvGXckJAepvNXH/9v0Eak iABSzezodLLJXXEZICFSF1QMJmnC+u/JRpL0F4Xfj9cnk4UdTHyDInaq2Qh5iyX55ZCi AvSA==
X-Gm-Message-State: AOPr4FUxYqBtiKgCN/GOsjhbHSKEqjrm8bAde6RBvKhuJI5ZAcG3r/GZj8QUifzUCiaqmmQKDxPhml3GB/NI+g==
MIME-Version: 1.0
X-Received: by 10.157.12.168 with SMTP id b37mr9738634otb.4.1461960503302; Fri, 29 Apr 2016 13:08:23 -0700 (PDT)
Received: by 10.157.36.81 with HTTP; Fri, 29 Apr 2016 13:08:23 -0700 (PDT)
In-Reply-To: <CAHsGAOKFb_McQtFT3XgJs5Ju47=sBS9TERvSFocaOyaJr5g6xg@mail.gmail.com>
References: <CAHsGAOKFb_McQtFT3XgJs5Ju47=sBS9TERvSFocaOyaJr5g6xg@mail.gmail.com>
Date: Fri, 29 Apr 2016 13:08:23 -0700
Message-ID: <CAHsGAOJoJn+BGaFkeCq6gnC2zQaNcFLLzUSJGPzHmOd=-vtKtA@mail.gmail.com>
From: Ajay L <ajayl.bro@gmail.com>
To: idr@ietf.org
Content-Type: multipart/alternative; boundary="001a1140af66799df40531a53452"
Archived-At: <http://mailarchive.ietf.org/arch/msg/idr/CeDRHUYFr2FdH6kP5wv5wuin4QE>
Subject: Re: [Idr] Question about BGP mandatory attribute missing behavior
X-BeenThere: idr@ietf.org
X-Mailman-Version: 2.1.17
Precedence: list
List-Id: Inter-Domain Routing <idr.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/idr>, <mailto:idr-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/idr/>
List-Post: <mailto:idr@ietf.org>
List-Help: <mailto:idr-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/idr>, <mailto:idr-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 29 Apr 2016 20:08:26 -0000

The section on NOTIFICATION message says that BGP connection is closed
immediately after sending it. So in my scenario, looks like the expected
behavior is to send NOTIFICATION message with details of the first detected
missing mandatory attribute and close the connection. Please let me know if
this interpretation is not correct

4.5 <https://tools.ietf.org/html/rfc4271#section-4.5>.  NOTIFICATION
Message Format

   A NOTIFICATION message is sent when an error condition is detected.
   The BGP connection is closed immediately after it is sent.



Thanks

Ajay


On Fri, Apr 29, 2016 at 11:32 AM, Ajay L <ajayl.bro@gmail.com> wrote:

> Hi Experts,
>
> Had a question about expected behavior about error handling scenario for
> an BGP implementation
>
> Per RFC 4271, if mandatory path attribute is not present in the UPDATE
> message, NOTIFICATION message with appropriate error code and subcode must
> be generated. If multiple mandatory path attributes are missing (e.g.
> ORIGIN and AS_PATH), is the expected behavior to generate multiple separate
> NOTIFICATION messages one for each missing attribute, or just
> one NOTIFICATION message for the first detected missing attribute?
>
>    If any of the well-known mandatory attributes are not present, then
>    the Error Subcode MUST be set to Missing Well-known Attribute.  The
>    Data field MUST contain the Attribute Type Code of the missing,
>    well-known attribute.
>
>
> Thanks
>
> Ajay
>
>