From mboxrd@z Thu Jan 1 00:00:00 1970 From: Moshe Yudkowsky Subject: Re: Unable to eradicate previous version of device information, even with zero-superblock and dd Date: Mon, 28 Jan 2008 13:18:48 -0600 Message-ID: <479E2A98.7010908@pobox.com> References: <479DEF34.70306@pobox.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <479DEF34.70306@pobox.com> Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids > QUESTIONS: > > 1. If I create a device called /dev/md/all, should I expect that mdadm > will create a device called /dev/md/127, and that mdadm --detail --scan > will report it as /dev/md127 or something similar? That's still happening. However: > 2. How can I completely eradicate all traces of previous work, given > that zero-superblock and dd on the drives that make up the array doesn't > seem to erase previous information? Answer: In order for the md drives to be started on a reboot, upgrade-initramfs places information about the current configuration into boot configuration. In order to eradicate everything, stop all arrays, comment out any ARRAY lines in mdadm.conf, remove all md device files, and then issue update-initramfs This cleans out the information that's hidden inside the /boot area. On the next reboot, no extraneous md files are present. It's then possible to issue an mdadm --create /dev/md/all that will create the appropriate md devices automatically with proper major and minor device numbers. To get the md device started correctly at init time, I seem to require the use of update-initramfs. I will investigate further when I've got some time... -- Moshe Yudkowsky * moshe@pobox.com * www.pobox.com/~moshe "The odds are good, but the goods are odd." -- Alaskan women, on the high ratio of men to women in Alaska