From mboxrd@z Thu Jan 1 00:00:00 1970 From: Duncan Laurie Subject: Re: Problems with RAID1 on cobalt raq3 Date: 19 Aug 2002 20:56:41 -0700 Sender: linux-raid-owner@vger.kernel.org Message-ID: <1029815801.7736.13.camel@atherton> References: <200208172056.g7HKuHm05754@raq.iceblink.org> <1029625780.14769.134.camel@atherton> <20020819083834.GM26818@jinny.ie> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20020819083834.GM26818@jinny.ie> To: valen@tuatha.org Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids On Mon, 2002-08-19 at 01:38, John P. Looney wrote: > > First off set_boot_dev was used to set the boot device to hda2 (I > tryed hda1, and as you pointed out, you can't move the root device > easily to hda2 later). > > I had originally planned that hda1 was /boot and hda2 was / - in the end, > to get *anything* booting, I'd to copy the /boot files into a /boot > directory on the / filesystem, and write off hda1 as a waste of disk > space. I think you want this to be md1, but to do that and have the kernel on a separate device (not a member of the raid set) will require you to override the root device for the ROM kernel with set_lparams. I was incorrect in saying that "set_boot_dev md1" does not have the same effect as "set_params root=/dev/md1", what I was seeing is actually a bug in the ROM. When you run "set_boot_dev md1" it updates the major/minor bytes in CMOS, but it does not set the variable that is used to create the zero-page. This means it will have the stale value until it is rebooted. (this is with a 2.9.x ROM, I am not sure about 2.3.40) > Woo-hoo. Exactly what I wanted. I think. > > So, do I do > > set_boot_dev hda1 (/boot) > set_params "root=/dev/md0 ro" > > And that should do what I've been trying to do ? Or do I have to change > the paramters to the ROM kernel also ? I would try this: set_boot_dev md1 [reboot here - bug workaround] set_lparams root=/dev/hda1 (this is assuming hda1 is /boot, and hda2+hdg1=md1 is /) The problem with this solution is you no longer get the ability to boot autonomously. The different root device is not saved in CMOS so has to be re-entered each time. -duncan