From mboxrd@z Thu Jan 1 00:00:00 1970 From: Veedar Hokstadt Subject: Re: mdadm -E won't examine loop back device, works ok on source disk Date: Mon, 23 Apr 2012 00:46:16 -0400 Message-ID: References: <20120423075816.6d21afe8@notabene.brown> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20120423075816.6d21afe8@notabene.brown> Sender: linux-raid-owner@vger.kernel.org To: NeilBrown Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids Thanks for your reply but setting IMSM_NO_PLATFORM seems to have no eff= ect... % export IMSM_NO_PLATFORM=3D1 % echo $IMSM_NO_PLATFORM 1 % mdadm -V mdadm - v3.2.3 - 23rd December 2011 % mdadm -E -v /dev/loop2 mdadm: No md superblock detected on /dev/loop2. % export IMSM_NO_PLATFORM=3D"" % echo $IMSM_NO_PLATFORM % mdadm -E -v /dev/loop2 mdadm: No md superblock detected on /dev/loop2. And trying to assemble fails... export IMSM_NO_PLATFORM=3D1 % mdadm --assemble /dev/md0 /dev/loop1 /dev/loop2 mdadm: Cannot assemble mbr metadata on /dev/loop1 mdadm: /dev/loop1 has no superblock - assembly aborted Regards, V On Sun, Apr 22, 2012 at 5:58 PM, NeilBrown wrote: > On Sun, 22 Apr 2012 17:00:04 -0400 Veedar Hokstadt = wrote: > >> Consider a SATA drive /dev/sdb which is a member of an imsm RAID0 ar= ray... >> >> % sum /dev/sdb >> 25645 156290904 >> >> The drive was imaged to a file without error and mounted as a loopba= ck device... >> >> % sum /dev/loop2 >> 25645 156290904 >> >> The checksums match as expected. But I can not examine the loopback = I get.... >> >> % mdadm =A0-E -v /dev/loop2 >> mdadm: No md superblock detected on /dev/loop2. >> >> But I can examine the physical source drive /dev/sdb... >> >> % mdadm =A0-E -v /dev/sdb >> /dev/sdb: >> =A0 =A0 =A0 =A0 =A0 Magic : Intel Raid ISM Cfg Sig. >> =A0 =A0 =A0 =A0 Version : 1.0.00 >> =A0 =A0 Orig Family : e92a11d9 >> =A0 =A0 =A0 =A0 =A0Family : e92a11d9 >> =A0 =A0 =A0Generation : 00001608 >> =A0 =A0 =A0 =A0 =A0 =A0UUID : 25137636:2ff64e75:10ae5444:4e8f609b >> =A0 =A0 =A0 =A0Checksum : e1237b20 correct >> =A0 =A0 MPB Sectors : 1 >> =A0 =A0 =A0 =A0 =A0 Disks : 2 >> =A0 =A0RAID Devices : 1 >> >> =A0 Disk01 Serial : 8068C3QVT >> =A0 =A0 =A0 =A0 =A0 State : active >> =A0 =A0 =A0 =A0 =A0 =A0 =A0Id : 00010000 >> =A0 =A0 Usable Size : 312577294 (149.05 GiB 160.04 GB) >> >> [Volume0]: >> =A0 =A0 =A0 =A0 =A0 =A0UUID : 72acd5fa:35c5a901:995af79b:83a29de1 >> =A0 =A0 =A0RAID Level : 0 >> =A0 =A0 =A0 =A0 Members : 2 >> =A0 =A0 =A0 This Slot : 1 >> =A0 =A0 =A0Array Size : 625154048 (298.10 GiB 320.08 GB) >> =A0 =A0Per Dev Size : 312577283 (149.05 GiB 160.04 GB) >> =A0 Sector Offset : 0 >> =A0 =A0 Num Stripes : 1221004 >> =A0 =A0 =A0Chunk Size : 128 KiB >> =A0 =A0 =A0 =A0Reserved : 0 >> =A0 Migrate State : idle >> =A0 =A0 =A0 Map State : normal >> =A0 =A0 Dirty State : clean >> >> =A0 Disk00 Serial : 809BC541T >> =A0 =A0 =A0 =A0 =A0 State : active failed >> =A0 =A0 =A0 =A0 =A0 =A0 =A0Id : 00000000 >> =A0 =A0 Usable Size : 312577294 (149.05 GiB 160.04 GB) >> >> I'm trying to recover data from a failed RAID0. >> I can successfully reassemble the RAID0 from the image files using >> other proprietary recovery software. >> But I would like to get it working with mdadm if at all possible. >> Any ideas? >> > > Try setting =A0IMSM_NO_PLATFORM in the environment: > > =A0IMSM_NO_PLATFORM=3D1 mdadm -E -v /dev/loop2 > > or > > =A0export IMSM_NO_PLATFORM=3D1 > =A0mdadm -E -v /dev/loop2 > > I think this is fixed in more recent mdadm. =A0You still need IMSM_NO= _PLATFORM > to create or assemble an array, but not just to look at it. > > NeilBrown > > -- To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html