From nobody Thu Sep 16 06:33:58 2021 X-Original-To: freebsd-net@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id B1AB317C6F14 for ; Thu, 16 Sep 2021 06:34:06 +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 4H96k63vbxz51VX; Thu, 16 Sep 2021 06:34:06 +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 BCDD0E6079; Thu, 16 Sep 2021 08:33:58 +0200 (CEST) Date: Thu, 16 Sep 2021 08:33:58 +0200 (CEST) Message-Id: <20210916.083358.257871963.sthaug@nethelp.no> To: karels@freebsd.org Cc: bzeeb-lists@lists.zabbadoz.net, freebsd-net@freebsd.org Subject: Re: change to deprecate broadcast on host 0 of a subnet From: sthaug@nethelp.no In-Reply-To: <202109152318.18FNI24k082607@mail.karels.net> References: <202109152318.18FNI24k082607@mail.karels.net> X-Mailer: Mew version 6.7 on Emacs 26 / Mule 6.0 (HANACHIRUSATO) List-Id: Networking and TCP/IP with FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-net List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-net@freebsd.org Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4H96k63vbxz51VX X-Spamd-Bar: ---- Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[] X-Spam: Yes X-ThisMailContainsUnwantedMimeParts: N >> I would prefer if the current behaviour stayed default (would also MFC >> better) >> and then flip if this will indeed go anywhere. > > I considered that, but I think that the current behavior is simply > wrong. We broadcast packets to the lowest address on the net, but > we don't receive these broadcasts as such. I was surprised to find > that we were still broadcasting these packets. I can't think of any > reason we should do that. > > Any other opinions on the default setting of the sysctl? I welcome a change to stop broadcasting the lowest address on a subnet. Yes this should have been done years ago. Steinar Haug, Nethelp consulting, sthaug@nethelp.no