IETF Logo Mail Archive

Re: [Idr] TCP & BGP: Some don't send terminate BGP when holdtimer expired, because TCP recv window is 0

"Jakob Heitz (jheitz)" <jheitz@cisco.com> Sat, 12 December 2020 14:07 UTC

Return-Path: <jheitz@cisco.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 CD9CA3A0BE7 for <idr@ietfa.amsl.com>; Sat, 12 Dec 2020 06:07:09 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -9.619
X-Spam-Level:
X-Spam-Status: No, score=-9.619 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HTML_MESSAGE=0.001, RCVD_IN_MSPIKE_H4=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_PASS=-0.001, URIBL_BLOCKED=0.001, USER_IN_DEF_DKIM_WL=-7.5] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=cisco.com header.b=ljODwsNT; dkim=pass (1024-bit key) header.d=cisco.onmicrosoft.com header.b=P5RhkzhL
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 tv1H60608pIo for <idr@ietfa.amsl.com>; Sat, 12 Dec 2020 06:07:07 -0800 (PST)
Received: from rcdn-iport-8.cisco.com (rcdn-iport-8.cisco.com [173.37.86.79]) (using TLSv1.2 with cipher DHE-RSA-SEED-SHA (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 1D5F03A0BE2 for <idr@ietf.org>; Sat, 12 Dec 2020 06:07:07 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cisco.com; i=@cisco.com; l=9537; q=dns/txt; s=iport; t=1607782026; x=1608991626; h=from:to:cc:subject:date:message-id:references: in-reply-to:mime-version; bh=lTVyVAkgIVkl2ncN597wHq+IzVtNiiqRLH3qn57tTho=; b=ljODwsNT7s8GASvs7H12GkbaTFJRAMDXP3hcrreCmX7d73idMBJWci95 KbuKrYXzCpODuSqUd4qds2ZA2zO0D34r+SUfLce6DwdpPov8S8AJUUfPN jr2pXzBaZGjdT0vaZgUwmFDag6OOAVe69zzKM1QG//rqDGPWo8DDlVmO8 s=;
IronPort-PHdr: 9a23:iLaNXhDZz3lG2URoov4sUyQJPHJ1sqjoPgMT9pssgq5PdaLm5Zn5IUjD/qw00g3TVJ7J9vECjefK4OjsWm0FtJCGtn1KMJlBTAQMhshemQs8SNWEBkv2IL+PDWQ6Ec1OWUUj8yS9Nk5YS9z3fE/PoTu04CJBUhn6PBB+c+LyHIOahs+r1ue0rpvUZQgAhDe0bb5oahusqgCEvcgNiowkIaE0mRY=
X-IronPort-Anti-Spam-Filtered: true
X-IronPort-Anti-Spam-Result: A0BcAgA8zdRf/5pdJa1iGwEBAQEBAQEBBQEBARIBAQEDAwEBAYIPgSMvIy4HdVsvLoQ+g0gDjS8ljw6FDoRxgUKBEQNUCwEBAQ0BARgBCgoCBAEBhEoCF4FoAiU4EwIDAQELAQEFAQEBAgEGBHGFYQyFcwIEAQEQER0BASwLAQ8CAQgOLQQDAgICJQsUEQIEDgUigwQBgX5XAy4BDp81AoE8iGl2gTKDBAEBBYEzAYNrGIIQCYE4gnWDeYZZG4FBP4ERJwwQglU+gX9eAQGBRUcRglkzgiyCQU5pBQFaKlJYCDePJYM2hyqDMoh5kTYKgnSJIpImAx+iPJ8PkU8PhDwCBAIEBQIOAQEFgW0jgVdwFTsqAS+BWwEBMglHFwINjiE3gXGBSYUUhUR0NwIGAQkBAQMJfIkPXwEB
X-IronPort-AV: E=Sophos;i="5.78,414,1599523200"; d="scan'208,217";a="838749096"
Received: from rcdn-core-3.cisco.com ([173.37.93.154]) by rcdn-iport-8.cisco.com with ESMTP/TLS/DHE-RSA-SEED-SHA; 12 Dec 2020 14:07:05 +0000
Received: from XCH-ALN-003.cisco.com (xch-aln-003.cisco.com [173.36.7.13]) by rcdn-core-3.cisco.com (8.15.2/8.15.2) with ESMTPS id 0BCE75lm023249 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=FAIL); Sat, 12 Dec 2020 14:07:05 GMT
Received: from xhs-aln-001.cisco.com (173.37.135.118) by XCH-ALN-003.cisco.com (173.36.7.13) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Sat, 12 Dec 2020 08:07:05 -0600
Received: from xhs-rtp-001.cisco.com (64.101.210.228) by xhs-aln-001.cisco.com (173.37.135.118) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Sat, 12 Dec 2020 08:07:04 -0600
Received: from NAM10-DM6-obe.outbound.protection.outlook.com (64.101.32.56) by xhs-rtp-001.cisco.com (64.101.210.228) with Microsoft SMTP Server (TLS) id 15.0.1497.2 via Frontend Transport; Sat, 12 Dec 2020 09:07:04 -0500
ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=KnkPmjZjS1COxOy1FFJ1WsfKBOJF2LLTRC8dSsVtHJSdT/UbBUb3rhy/EWVeKp6CYxIsuaZ+Z3hbfw3EVI1+n4e+grrH69vpT8yIHyj0995VLfm1y94oVHKukQZ8wqlcxVYObM0LxuzmCRp23ltHcD9QqVuWAZUME/lSdqk1W2BzRT/KjPkBJwqvqEvuOyFIkj4wfoiSNy6Tl6Ru4rj10rzYh/MNn09DeHL40g5sO4wDmgvOaXC/a3J3Tr0gk5PN2FMbJ/xrR/NzBLQ0WLsX6WTePkEgdLJyarvIvf1mWy13cbCx8q99J2lPClw5gY6cx0bA+OqBjsxOWY0fZqdlQA==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=lTVyVAkgIVkl2ncN597wHq+IzVtNiiqRLH3qn57tTho=; b=bnZQ0JRa8dcV2vWm3MIODukBxsbq8lEB4thca7SGZuDtSMt3LHvcCuWsrm77nj38gyi9Jk57fbLc48RfS3k6ugr83VtjT8Y3aCgNJIzmUmLFNryjQLBFSABMezfmnLddKLJCGTtx9haGBSVw1RYfe3HjBNidUTgJ7c/HM5YOmzRL5GT0BsRAKfINfUxF091E2nJyqG9OjnCHV5D7+dwg37jv0EaJHl+01hRfQvaDClyJESwOYb2BF7KTCqCPo7t6TFERb+7HsLI/UAy8Hv0KWNQLcHXCOtsUoYihg9am1sLyatCGIMdAzc+zIrpNA8zB0YRcxrQJqHmXxsoYmC1prw==
ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=cisco.com; dmarc=pass action=none header.from=cisco.com; dkim=pass header.d=cisco.com; arc=none
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cisco.onmicrosoft.com; s=selector2-cisco-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=lTVyVAkgIVkl2ncN597wHq+IzVtNiiqRLH3qn57tTho=; b=P5RhkzhLiPmpYhwsVT8BxuUnkWOO1lmNUF6BgboUfltbvF3iNGSosv5EppOiQJILTATP9Im90NL3DZILVsDS//vCFy0u6J+XoYS4D8+S9ldScX3X9Eb//B8ZFI+oFSrZtsMOTv7bKnfOem42dV48Mgo0lk1XbD+Rj0mEfwIxAmU=
Received: from BYAPR11MB3207.namprd11.prod.outlook.com (2603:10b6:a03:7c::14) by BYAPR11MB3575.namprd11.prod.outlook.com (2603:10b6:a03:b3::33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3654.15; Sat, 12 Dec 2020 14:07:03 +0000
Received: from BYAPR11MB3207.namprd11.prod.outlook.com ([fe80::2581:444d:50af:1701]) by BYAPR11MB3207.namprd11.prod.outlook.com ([fe80::2581:444d:50af:1701%4]) with mapi id 15.20.3632.023; Sat, 12 Dec 2020 14:07:03 +0000
From: "Jakob Heitz (jheitz)" <jheitz@cisco.com>
To: Christoph Loibl <c@tix.at>
CC: Robert Raszuk <robert@raszuk.net>, "idr@ietf.org" <idr@ietf.org>
Thread-Topic: [Idr] TCP & BGP: Some don't send terminate BGP when holdtimer expired, because TCP recv window is 0
Thread-Index: AQHWz/PZ/nZ2Wy6ptUq1oN4xA4s39qnzMNSAgABM7oCAAAJ3QA==
Date: Sat, 12 Dec 2020 14:07:03 +0000
Message-ID: <1B4E7C9D-BBFE-4865-87F9-133ACE55D122@cisco.com>
References: <X9PHRuGndvsFzQrG@bench.sobornost.net> <CAOj+MME4OHmoqJfzNQ4Tj6+wCd1kJVHPfJsDbk_+Xh8fh5G8Dg@mail.gmail.com>, <6F7C5906-51A8-43C2-8AEC-3DB74CB9941F@tix.at>
In-Reply-To: <6F7C5906-51A8-43C2-8AEC-3DB74CB9941F@tix.at>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
authentication-results: raszuk.net; dkim=none (message not signed) header.d=none;raszuk.net; dmarc=none action=none header.from=cisco.com;
x-originating-ip: [2601:647:5701:46e0:490:2dda:e9dd:b651]
x-ms-publictraffictype: Email
x-ms-office365-filtering-correlation-id: c3767611-edf6-4df8-b5fc-08d89ea73382
x-ms-traffictypediagnostic: BYAPR11MB3575:
x-microsoft-antispam-prvs: <BYAPR11MB3575CBCB2E12844EEF10BDDCC0C90@BYAPR11MB3575.namprd11.prod.outlook.com>
x-ms-oob-tlc-oobclassifiers: OLM:9508;
x-ms-exchange-senderadcheck: 1
x-microsoft-antispam: BCL:0;
x-microsoft-antispam-message-info: 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
x-forefront-antispam-report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:BYAPR11MB3207.namprd11.prod.outlook.com; PTR:; CAT:NONE; SFS:(366004)(346002)(136003)(376002)(86362001)(54906003)(508600001)(2616005)(8676002)(6916009)(166002)(186003)(64756008)(71200400001)(66556008)(6506007)(33656002)(8936002)(66446008)(6486002)(966005)(36756003)(6512007)(2906002)(53546011)(83380400001)(5660300002)(83080400002)(4326008)(76116006)(66946007)(66476007)(781001)(45980500001); DIR:OUT; SFP:1101;
x-ms-exchange-antispam-messagedata: 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
x-ms-exchange-transport-forked: True
Content-Type: multipart/alternative; boundary="_000_1B4E7C9DBBFE486587F9133ACE55D122ciscocom_"
MIME-Version: 1.0
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-AuthSource: BYAPR11MB3207.namprd11.prod.outlook.com
X-MS-Exchange-CrossTenant-Network-Message-Id: c3767611-edf6-4df8-b5fc-08d89ea73382
X-MS-Exchange-CrossTenant-originalarrivaltime: 12 Dec 2020 14:07:03.2567 (UTC)
X-MS-Exchange-CrossTenant-fromentityheader: Hosted
X-MS-Exchange-CrossTenant-id: 5ae1af62-9505-4097-a69a-c1553ef7840e
X-MS-Exchange-CrossTenant-mailboxtype: HOSTED
X-MS-Exchange-CrossTenant-userprincipalname: yGw8bPCtaNnLogzQX+ysP37dlAiWkwrdVhuz7ESTy7MSrgfXDwtBvL6rm7ZGpLUgiJKHyiQ3kEEqHlu05fjFww==
X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR11MB3575
X-OriginatorOrg: cisco.com
X-Outbound-SMTP-Client: 173.36.7.13, xch-aln-003.cisco.com
X-Outbound-Node: rcdn-core-3.cisco.com
Archived-At: <https://mailarchive.ietf.org/arch/msg/idr/JeJozecqvH06RPAEDHx_CUbxKjM>
Subject: Re: [Idr] TCP & BGP: Some don't send terminate BGP when holdtimer expired, because TCP recv window is 0
X-BeenThere: idr@ietf.org
X-Mailman-Version: 2.1.29
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: Sat, 12 Dec 2020 14:07:10 -0000

No.

Regards,
Jakob.


On Dec 12, 2020, at 6:01 AM, Christoph Loibl <c@tix.at> wrote:

 Hi,

Isn’t it save to assume that if a system cannot send any messages to its BGP-neighbor (for whatever reason) for HOLD TIME seconds, that the neighbor on the other side has by that time already declared the BGP session dead (is already “trying" to deliver a NOTIFICATION and has removed the routes from its RIB). If this is the case I see no point in trying to keep the session alive, because it will *always* sooner or later lead to a new session-setup + flapping routes. The BGP session (if the NOTIFICATION is queued) cannot recover from that state anymore (can it?) and is useless, even if there are chances that messages may get delivered later.

Cheers Christoph

--
Christoph Loibl
c@tix.at<mailto:c@tix.at> | CL8-RIPE | PGP-Key-ID: 0x4B2C0055 | http://www.nextlayer.at



On 12.12.2020, at 10:22, Robert Raszuk <robert@raszuk.net<mailto:robert@raszuk.net>> wrote:


I went back and reread the thread:

   https://mailarchive.ietf.org/arch/msg/idr/q0Sx5d3zZjfOmOQ4lO2OZAHh9Lc/

Shouldn't it be better if we first ask implementations to provide show command/api to list all peers and min-max durations of TCP Window being 0 without actually doing any automagic RST/NOTIFICATION/FIN ?

This could allow to better understand which peers are getting behind in their control plane and perhaps also allow to set the RST timer under such conditions by operator? If he chooses this to be equal to HOLD TIME so be it but I am not sure this would be universally an optimal choice.

Along the same lines we should perhaps also list per BGP peer number of DUPLICATE ACKS, RETRANSMISSIONS etc ...

Are there implementations already deployed in DFZ allowing such data to be displayed per each BGP peer ?

Thx,
Robert.

_______________________________________________
Idr mailing list
Idr@ietf.org<mailto:Idr@ietf.org>
https://www.ietf.org/mailman/listinfo/idr

_______________________________________________
Idr mailing list
Idr@ietf.org
https://www.ietf.org/mailman/listinfo/idr

v2.23.0 | Report a Bug | By Email