From owner-freebsd-hackers Tue Mar 3 07:12:44 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id HAA23114 for freebsd-hackers-outgoing; Tue, 3 Mar 1998 07:12:44 -0800 (PST) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from post-ofc04.srv.cis.pitt.edu (root@post-ofc04.srv.cis.pitt.edu [136.142.185.11]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id HAA23052 for ; Tue, 3 Mar 1998 07:12:34 -0800 (PST) (envelope-from jddst19+@pitt.edu) Received: from dysphoria.pain.com (ehdup-c3-8.rmt.net.pitt.edu [136.142.20.178]) by post-ofc04.srv.cis.pitt.edu with ESMTP (8.8.8/8.8.8/cispo-7.2.1.10) ID ; Tue, 3 Mar 1998 10:12:21 -0500 (EST) Message-Id: <24192.888937362.858108.15866@> Date: Tue, 3 Mar 1998 10:02:42 -0500 From: John Duncan Subject: Re: CCD & booting on / To: , Reply-To: John Duncan X-Importance: normal X-Sensitivity: normal X-Priority: normal X-Mailer: TeamWARE Embla 2.03, Final, Build: 74 MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Content-Disposition: inline Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Philippe Regnauld: >Stop me when I'm falling over the edge :-) > >I'm interested in getting a machine with having every partition >as a CCD mirror -- including /. > >I'm aware of the usual problem of having / as a ccd: the bootblocks >won't be able to read the partition, etc... > >But I remember, on one setup using _mirroring_ (and only in that >case of course) where one of the disks died, I just rebooted >single user on the remaining disk, changed the ccdconfig >line to remove the defective disk, and ran ccdconfig with the same >options -- and I was up and running again, with a 1-sided mirror :-) > >My question is: is there no workaround/unspeakable hack that >could be made, with CCD in the kernel, for the bootblocks to read >from the first of an N-part mirror, just to get past the boot ? > >Yeah, I could of course have / = 2 MB and symlink everything >somewhere else :-P if you could spare a cylinder on each disk, you could have a kernel load from the first cylinder on the first disk past the bootsector and then use unionfs for that partition (readonly) and ccd. The kernel would also be on a readonly filesystem. You'd have to keep a backup of the kernel. Minimally, you'd need to put some parts of /etc on the small partition, I think. Someone else would be better at telling you exactly which parts. -John To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message