From owner-freebsd-net@freebsd.org  Sun Mar 18 09:53:16 2018
Return-Path: <owner-freebsd-net@freebsd.org>
Delivered-To: freebsd-net@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id 43EBD270
 for <freebsd-net@mailman.ysv.freebsd.org>;
 Sun, 18 Mar 2018 09:53:16 +0000 (UTC)
 (envelope-from sthaug@nethelp.no)
Received: from bizet.nethelp.no (bizet.nethelp.no [195.1.209.33])
 by mx1.freebsd.org (Postfix) with ESMTP id C6FA86865A
 for <freebsd-net@freebsd.org>; Sun, 18 Mar 2018 09:53:15 +0000 (UTC)
 (envelope-from sthaug@nethelp.no)
Received: from localhost (bizet.nethelp.no [IPv6:2001:8c0:9e04:500::1])
 by bizet.nethelp.no (Postfix) with ESMTP id C6354E6047;
 Sun, 18 Mar 2018 10:53:07 +0100 (CET)
Date: Sun, 18 Mar 2018 10:53:07 +0100 (CET)
Message-Id: <20180318.105307.74674158.sthaug@nethelp.no>
To: "Rodney W. Grimes" <freebsd-rwg@pdx.rh.CN85.dnsmgr.net>
Cc: "Alexander V. Chernikov" <melifaro@ipfw.ru>, freebsd-net@freebsd.org
Subject: Re: Does FreeBSD do proactive ARP refresh?
From: sthaug@nethelp.no
In-Reply-To: <201803180938.w2I9cvJs006183@pdx.rh.CN85.dnsmgr.net>
References: <3023141521364867@web33j.yandex.ru>
 <201803180938.w2I9cvJs006183@pdx.rh.CN85.dnsmgr.net>
X-Mailer: Mew version 3.3 on Emacs 21.3 / Mule 5.0 (SAKAKI)
Mime-Version: 1.0
Content-Type: Text/Plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
X-BeenThere: freebsd-net@freebsd.org
X-Mailman-Version: 2.1.25
Precedence: list
List-Id: Networking and TCP/IP with FreeBSD <freebsd-net.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/freebsd-net>,
 <mailto:freebsd-net-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-net/>
List-Post: <mailto:freebsd-net@freebsd.org>
List-Help: <mailto:freebsd-net-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/freebsd-net>,
 <mailto:freebsd-net-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sun, 18 Mar 2018 09:53:16 -0000

> > Side note: if one has monitoring which does ICMP checks, it will mask the issue because icmp replies don't use route caching.
> > Typical story  when the observer changes the state of an observed object :-).
> 
> Also perhaps why it has not been reported before, as other side effects
> have caused it to be a pretty invisible issue.

The reason I discovered this is because I was running longer (1 hour
or more) iperf3 sessions, and I got some small but regular packet loss
that I couldn't remember having seen before. Which may be because my
previous longer iperf3 sessions had been with FreeBSD 9.3-STABLE.

Steinar Haug, Nethelp consulting, sthaug@nethelp.no