From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Pittman Subject: Re: raid1: All my data completely vanished into the void Date: Wed, 28 Dec 2005 17:44:12 +1100 Message-ID: <87ek3xsoub.fsf@rimspace.net> References: <200512280030.51387.mlaks@verizon.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Sebastian Kuzminsky writes: > Mitchell Laks wrote: >> What does doing >> >> mdadm -Cv -n2 -l1 /dev/md0 /dev/sda /dev/sdb >> >> do to the partition tables??? >> (And why can I still access the data if I messed up the partitions??? very >> odd). >> Can you point me at an explanation of the effects of what I did? > > I'd expect that command to overwrite the partition table with the > MD metadata, or at least put the partition table at risk of being > overwritten later. Nope: the MD metadata lives at the end of the disk, not the start, so your partition table would still be there when the filesystem wrote over the first block of the disk... ...and, if the partition table lived through that, I guess the filesystem doesn't use (or respects) that block itself. Daniel