From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phil Turmel Subject: Re: Fwd: manually destriping a 4 drive raid5 with one missing drive Date: Sun, 25 Oct 2015 18:47:35 -0400 Message-ID: <562D5C07.40501@turmel.org> References: <87fv19m7he.fsf@notabene.neil.brown.name> <20151023155324.GA2555@lazy.lzy> <562A7333.9010702@turmel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Marek Cc: Linux-RAID List-Id: linux-raid.ids Hi Marek, On 10/23/2015 04:46 PM, Marek wrote: > On Fri, Oct 23, 2015 at 7:49 PM, Phil Turmel wrote: >> On 10/23/2015 12:20 PM, Marek wrote: >>> Not sure if it's destrip or destripe but it's basically like puzzle >>> you take a block from each drive according to the layout you are using >>> e.g. Left symmetric and then write it down in that order computing >>> missing blocks from parity blocks - this way you would write an image >>> which you can mount without using mdadm. Data restoration companies >>> are using this technique. >> >> No special tool required. Obtain a new drive big enough to hold your >> entire array and 'dd' from /dev/mdX to your new drive. > dd from mdX doesn't work i tried it even with testdisk, what you get > is mixed up data, incomplete files. Well, that suggests you've done more than just a forced resync. Pretty much the only way to get this is to screw up the device order with "mdadm --create --assume-clean" You'll need to provide a great deal of data about your array and precisely what you've done to it. > { Google mail on iPad doesn't support plain text, who knew :/ } {Top-posting fixed. Gmail screws this up by default, too.} Phil