From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Wiegley Subject: Re: Why would a recreation cause a different number of blocks?? Date: Thu, 24 Apr 2014 22:02:05 -0700 Message-ID: <5359EC4D.7000308@csun.edu> References: <20140424070548.445497dd@netstation> <20140424194832.2d0a867f@netstation> <20140424203506.5fdee0d3@netstation> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Mikael Abrahamsson Cc: "linux-raid@vger.kernel.org" List-Id: linux-raid.ids I'll look into this. I kind of thought about that sort of thing and I went and installed ubuntu 12.04 which I thought was what I started this all with but I might have done it earlier than 12.04 and I might have used gentoo. are the mdadm defaults specific to mdadm version or would ubuntu and gentoo have specified different defaults in something like an /etc/defaults/ourmdadm.cfg? If it's mdadm then could I just grab old copies of mdadm sources and compile them one version after the other and try each one? Thanks, - Jeff On 4/24/2014 8:34 PM, Mikael Abrahamsson wrote: > On Thu, 24 Apr 2014, Jeff Wiegley wrote: > >> Why did my block counts change? The disk partitions weren't touched >> or changed at any point. Shouldn't I have gotten the same size? > > Defaults in mdadm has changed over time, so data offsets might be > different. In order to get the exact same data offset you need to use the > same mdadm version as was originally used, or at least know the values it > used and use mdadm 3.3 that allows you to specify these data at creation > time, > >> The created device isn't work. There is suppose to be luks encrypted >> volume there but luksOpen reports there is no luks header. (and there >> use to be). Would the odd change in size indicate total corruption? > > No, the change in size indicates that data offsets are not the same so > your beginning of volume is now in the wrong place. >