Re: [Ntp] NTS-KE server load pulse

Marcus Dansarie <marcus@dansarie.se> Thu, 01 February 2024 19:30 UTC

Return-Path: <marcus@dansarie.se>
X-Original-To: ntp@ietfa.amsl.com
Delivered-To: ntp@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id A186EC14F707 for <ntp@ietfa.amsl.com>; Thu, 1 Feb 2024 11:30:57 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.106
X-Spam-Level:
X-Spam-Status: No, score=-2.106 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, RCVD_IN_ZEN_BLOCKED_OPENDNS=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01, URIBL_BLOCKED=0.001, URIBL_DBL_BLOCKED_OPENDNS=0.001, URIBL_ZEN_BLOCKED_OPENDNS=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=dansarie.se
Received: from mail.ietf.org ([50.223.129.194]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id nx9r_e1GuBjL for <ntp@ietfa.amsl.com>; Thu, 1 Feb 2024 11:30:52 -0800 (PST)
Received: from mail.dansarie.se (mail.dansarie.se [IPv6:2a02:7aa0:5000::14a]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id ADDDFC14F6FB for <ntp@ietf.org>; Thu, 1 Feb 2024 11:30:51 -0800 (PST)
Received: by mail.dansarie.se (Postfix, from userid 117) id 313BB7E21E; Thu, 1 Feb 2024 19:30:46 +0000 (UTC)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dansarie.se; s=mail; t=1706815845; bh=T5Jik/uNzx5Wv+AOamSzi3xXKEbtAGPC7O07OzYXAxg=; h=Date:Subject:To:References:From:In-Reply-To:From; b=OZBCFDAmz5t8pKvj928Bw3x2+uwl4lFF587O6gXsh9QcGIBpFAOrvz2K2HHgpEDCw UGzOMHNineZEQsT3/LQdqpa71EFuIGYVo6P8agg4xeqndLjPc0R1IzRCjs2pmXXJUo rum3KSdHDS6GqQhWv2u9l12Izs9KpUsz2ie0t3zVQmb/FR8Obm+Nhyd8ZYv7i78zXw gsN9kVANq6+NI21EVPjnjqYkAdLXHi6I1Wr4UJo+S3Vgu5aq6QsSMIdEn0GE7StLO+ 2Ws72VsVRdOZom3FsaXXQMiJy5iezoI51hn7HASZJEq3KInH/u68zIHe10m9hmEZZs w3PegsZo7Sl0A==
Message-ID: <eb8a3b88-39b7-4dad-a129-1aa676c9baa8@dansarie.se>
Date: Thu, 01 Feb 2024 20:30:44 +0100
MIME-Version: 1.0
Content-Language: en-US, sv-SE
To: ntp@ietf.org
References: <20240131210135.62B2528C065@107-137-68-211.lightspeed.sntcca.sbcglobal.net>
From: Marcus Dansarie <marcus@dansarie.se>
In-Reply-To: <20240131210135.62B2528C065@107-137-68-211.lightspeed.sntcca.sbcglobal.net>
Content-Type: text/plain; charset="UTF-8"; format="flowed"
Content-Transfer-Encoding: 7bit
Archived-At: <https://mailarchive.ietf.org/arch/msg/ntp/3JswCP88fpXj6lploK-w5L960sc>
Subject: Re: [Ntp] NTS-KE server load pulse
X-BeenThere: ntp@ietf.org
X-Mailman-Version: 2.1.39
Precedence: list
List-Id: Network Time Protocol <ntp.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ntp>, <mailto:ntp-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ntp/>
List-Post: <mailto:ntp@ietf.org>
List-Help: <mailto:ntp-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ntp>, <mailto:ntp-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 01 Feb 2024 19:30:57 -0000

If clients implement a backoff as required by Section 4.2 of the RFC, 
the requests should be at least somewhat spread out when the NTS-KE 
server comes up again. If the NTS-KE server does go down from a load 
pulse, the backoff should help spread the load out even more that time.

I'm starting to think Mirja had a point when she fought us to have the 
backoff included...

Kind regards,
Marcus

On 2024-01-31 22:01, Hal Murray wrote:
> I'm assuming that a NTP server and its NTS-KE server are running on the same
> box and that the client doesn't reuse cookies.
> 
> Consider what happens if that box is down for X minutes.  If X is greater than
> 8 times a client's polling interval, the client will run out of cookies and go
> through NTS-KE again.
> 
> Are we going to run into troubles with the NTS-KE server getting overloaded
> when the server comes back up and all the clients jump on it trying to get new
> cookies?
> 
>