From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tim Southerwood Subject: Re: Loop devices to RAID? (was Re: In this partition scheme, grub does not find md information?) Date: Wed, 30 Jan 2008 15:56:11 +0000 Message-ID: <47A09E1B.5070705@dionic.net> References: <479F07E1.7060408@pobox.com> <479F0AAB.3090702@rabbit.us> <479F331F.7080902@msgid.tls.msk.ru> <479F3C74.1050605@rabbit.us> <479F42A5.8040007@msgid.tls.msk.ru> <20080129162640.GA16250@rap.rap.dk> <479F5882.8050400@msgid.tls.msk.ru> <20080129180101.GB19527@rap.rap.dk> <47A07D95.2030902@msgid.tls.msk.ru> <47A08E02.3000009@rabbit.us> <20080130152156.GA22131@rap.rap.dk> <47A0993F.8000005@rabbit.us> <47A09BBC.1000800@pobox.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <47A09BBC.1000800@pobox.com> Sender: linux-raid-owner@vger.kernel.org To: Moshe Yudkowsky Cc: Peter Rabbitson , linux-raid@vger.kernel.org List-Id: linux-raid.ids Moshe Yudkowsky wrote: > My mind boggles. I know how to mount an ISO as a loop device onto the > file system, but if you'd be so kind, can you give a super-brief > description on how to get a loop device to look like an actual partition > that can be made into a RAID array? I can see this software-only > solution as being quite interesting for testing in general. > I tried this a while back, IIRC the procedure was: 1) Make some empty files of the required length each. 2) Use losetup to mount each one onto a loop device (loop0-3 say). 3) Use /dev/loop[0-3] as component devices to mdadm as you would use any other device or partition. It is not necessary to partition the loop devices, use them whole. HTH Tim