From owner-freebsd-questions@FreeBSD.ORG Sun Dec 15 05:48:29 2013 Return-Path: Delivered-To: freebsd-questions@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 39635AB7 for ; Sun, 15 Dec 2013 05:48:29 +0000 (UTC) Received: from wonkity.com (wonkity.com [67.158.26.137]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id CA1F11A80 for ; Sun, 15 Dec 2013 05:48:28 +0000 (UTC) Received: from wonkity.com (localhost [127.0.0.1]) by wonkity.com (8.14.7/8.14.7) with ESMTP id rBF5mRAG034231; Sat, 14 Dec 2013 22:48:27 -0700 (MST) (envelope-from wblock@wonkity.com) Received: from localhost (wblock@localhost) by wonkity.com (8.14.7/8.14.7/Submit) with ESMTP id rBF5mQbi034228; Sat, 14 Dec 2013 22:48:26 -0700 (MST) (envelope-from wblock@wonkity.com) Date: Sat, 14 Dec 2013 22:48:26 -0700 (MST) From: Warren Block To: Eric Dynamic Subject: Re: concerning loader.conf(5) In-Reply-To: <52AD3C12.301@transbay.net> Message-ID: References: <52AD3C12.301@transbay.net> User-Agent: Alpine 2.00 (BSF 1167 2008-08-23) 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]); Sat, 14 Dec 2013 22:48:27 -0700 (MST) Cc: freebsd-questions@FreeBSD.org X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 15 Dec 2013 05:48:29 -0000 On Sat, 14 Dec 2013, Eric Dynamic wrote: > There's the issue where you move disks from installed system A to a > different motherboard > and the system can't boot because it remembers the old system's device > names. > Where is the fix for this documented? Labels are the easiest fix, a static name that sticks with a partition or filesystem regardless of changing device numbers. http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/geom-glabel.html GPT labels are the preferred method, although that section does not mention them yet. UFS labels work well also. > I examined /boot/defaults/loader.conf and I believe the lines in > question - for a /boot/loader.conf > file I would create as the override for the problem are these: > #currdev="disk1s1a" # Set the current device > #root_disk_unit="0" # Force the root disk unit number > #rootdev="disk1s1a" # Set the root filesystem > I'll guess that "rootdev" is all I need to specify, or possibly > "currdev" as well. > I have this nit to pick: the loader.conf man page does NOT describe > these labels at all, > and the Online Manual in describing the boot process makes no mention > of this mechanism, > either. The only one likely to be needed is vfs.root.mountfrom, which may need to be set to the UFS filesystem that contains /etc/fstab.