From owner-freebsd-current Tue Jan 7 7: 4:25 2003 Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 2906737B401 for ; Tue, 7 Jan 2003 07:04:24 -0800 (PST) Received: from spider.deepcore.dk (cpe.atm2-0-56339.0x50c6aa0a.abnxx2.customer.tele.dk [80.198.170.10]) by mx1.FreeBSD.org (Postfix) with ESMTP id 339E943ED8 for ; Tue, 7 Jan 2003 07:04:15 -0800 (PST) (envelope-from sos@spider.deepcore.dk) Received: (from sos@localhost) by spider.deepcore.dk (8.12.5/8.12.6) id h07F38hS044177; Tue, 7 Jan 2003 16:03:08 +0100 (CET) (envelope-from sos) From: Soeren Schmidt Message-Id: <200301071503.h07F38hS044177@spider.deepcore.dk> Subject: Re: mirrored root fs? In-Reply-To: <1041951264.3e1aea2012592@Mail.EnContacto.Net> To: eculp@encontacto.net Date: Tue, 7 Jan 2003 16:03:08 +0100 (CET) Cc: "current@FreeBSD.ORG" X-Mailer: ELM [version 2.4ME+ PL98b (25)] MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG It seems eculp@encontacto.net wrote: > Søren, > > This is a real temptation. Let me be sure that I'm understanding > correctly. I have an old machine, but running today's current, with only > one disk, ad0. Could I do the following? > > o- Add ad2 > o- run atacontrol create RAID1 ad0 ad2 source ad0 > o- change ad0s1a to ar0s1a through ad0s1f to ar0s1f in fstab > o- reboot and enjoy my new mirror. Exactly, modulo the "source ad0" bit which is not in atacontrol (yet), it will always the the first disk (ad0 here) in the mirror as the master to make the mirror from. > If ar0 were to die, I would just take it out connect ar2 and boot as ? > I could then do the same with a new mirror, I suppose? If one of the disks die, you can boot on the degraded mirror, one caveat is that your BIOS might not want to boot from "ad2" just from "ad0", if thats the case swap the drives, and boot... Then when you are up, atacontrol detach the failed device, swap it with a new one, atacontrol attach, atacontrol rebuild, voila... Another way is to boot the degraded mirror, then when its up you do a atacontrol delete to get rid of the mirror, remember to change your fstab back to adX instead of arX, and reboot... > If I'm understanding correctly, I could use any disk > ad0 as the mirror. > Is that correct? Yes, as it is currently it must be on another non-RAID controller, or the BIOS on there will get mighty confused only having part of a RAID config on it :) > One last question, what prompted you to preceed the patch with > "For those that are brave enough to play with this", where could > it come back and bit me? :-) Doing "stuff" to your root filesystems is always dangerous, so you have been warned :) -Søren To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message