From owner-freebsd-hackers@freebsd.org Mon Aug 31 13:00:27 2015 Return-Path: Delivered-To: freebsd-hackers@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 6EDE39C7343 for ; Mon, 31 Aug 2015 13:00:27 +0000 (UTC) (envelope-from wblock@wonkity.com) Received: from mailman.ysv.freebsd.org (mailman.ysv.freebsd.org [IPv6:2001:1900:2254:206a::50:5]) by mx1.freebsd.org (Postfix) with ESMTP id 553AD8D3 for ; Mon, 31 Aug 2015 13:00:27 +0000 (UTC) (envelope-from wblock@wonkity.com) Received: by mailman.ysv.freebsd.org (Postfix) id 546DC9C7342; Mon, 31 Aug 2015 13:00:27 +0000 (UTC) Delivered-To: hackers@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 540B59C7340 for ; Mon, 31 Aug 2015 13:00:27 +0000 (UTC) (envelope-from wblock@wonkity.com) Received: from wonkity.com (wonkity.com [67.158.26.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "wonkity.com", Issuer "wonkity.com" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 0FA1B8D2 for ; Mon, 31 Aug 2015 13:00:26 +0000 (UTC) (envelope-from wblock@wonkity.com) Received: from wonkity.com (localhost [127.0.0.1]) by wonkity.com (8.15.2/8.15.2) with ESMTPS id t7VD0IxB047310 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO) for ; Mon, 31 Aug 2015 07:00:18 -0600 (MDT) (envelope-from wblock@wonkity.com) Received: from localhost (wblock@localhost) by wonkity.com (8.15.2/8.15.2/Submit) with ESMTP id t7VD0Ib9047307 for ; Mon, 31 Aug 2015 07:00:18 -0600 (MDT) (envelope-from wblock@wonkity.com) Date: Mon, 31 Aug 2015 07:00:18 -0600 (MDT) From: Warren Block To: hackers@freebsd.org Subject: Re: Puzzle involving serial console and ...??!? In-Reply-To: <20150831030639.GH1153@albert.catwhisker.org> Message-ID: References: <20150831030639.GH1153@albert.catwhisker.org> User-Agent: Alpine 2.20 (BSF 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.4.3 (wonkity.com [127.0.0.1]); Mon, 31 Aug 2015 07:00:18 -0600 (MDT) X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 31 Aug 2015 13:00:27 -0000 On Sun, 30 Aug 2015, David Wolfskill wrote: > I may be going mad -- that's likely the simplest explanation, and > Occam's Razor would thus indicate that this hypothesis should be > accorded a degree of plausibility, at least. > > As described in , > I have my own quirky ways of upgrading FreeBSD systems, the basics > of which remain fundamentally unchanged for the last dozen years > (well, a few more than that, but...). In turn, much of that approach > was borrowed from one of my pre-FreeBSD experiences in an IBM > mainframe environment (as a "systems programmer"). > > What's causing me to question my tenuous grasp of reality is this: > Referencing the above-cited Web page, my build machine ("freebeast") > normally runs headless, and I use a cable to connect its serial > port to the serial port of one of my other machines ("albert"). > > By doing so, I have a working serial console (once the FreeBSD > loader gains control from the BIOS, at least)... half the time. > > I have determined that whether or not I have a functioning serial > console for freebeast depends on whether I boot albert from slice > 1 or slice 2: if from slice 1, it doesn't work; if from slice 2, > it does. > > Even when the contents of the 2 slices are functionally equivalent > (that is, the file systems of the 2 slices are as "the same" as a > "dump 0Lf | restore" pipeline can make them, except for a deliberate > difference in the contents of /etc/fstab (as the root and /usr file > systems are on different slices in the two cases)). Unless there is a newfs in there also, there could be additional files on the target filesystems. Maybe an mtree comparison or rsync -n would reveal differences. "nodump" flags and dump's -h flag is another possibility, although less likely.