From mboxrd@z Thu Jan 1 00:00:00 1970 From: Krekna Mektek Subject: Re: RAID 5 inaccessible - continued Date: Thu, 16 Feb 2006 17:42:49 +0100 Message-ID: <8b24c8b10602160842w5896390ap@mail.gmail.com> References: <8b24c8b10602130708p3e2f9a1dh@mail.gmail.com> <17393.42370.394254.464935@cse.unsw.edu.au> <8b24c8b10602140235s7a4ef1fam@mail.gmail.com> <43F1FFE1.2010107@h3c.com> <8b24c8b10602140918s136b5075s@mail.gmail.com> <43F2163A.6030302@dgreaves.com> <8b24c8b10602151218i43886b75h@mail.gmail.com> <43F3B119.1000800@dgreaves.com> <8b24c8b10602160632h59111c54u@mail.gmail.com> <8b24c8b10602160708j248c1752u@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Return-path: In-Reply-To: <8b24c8b10602160708j248c1752u@mail.gmail.com> Content-Disposition: inline Sender: linux-raid-owner@vger.kernel.org To: David Greaves , linux-raid@vger.kernel.org List-Id: linux-raid.ids Oh man! I've never been so happy! Wow. My array is back, with the dd_rescue which indeed came to the rescue. Since I've configured my LVM again, the raid Array is accessible again. Guys, many thanks for your help! dd_rescue is indeed something different then a dd conv=noerror, though I tried that one only once. I need to buy another 500GB disk now to _FIRST_ backup the whole thing. Krekna 2006/2/16, Krekna Mektek : > Whoops, sorry, I remember something about LVM... I've setup the system > with LVM, I'm sure of that. In that case I can't mount /dev/md0 of > course.. > > I need to find out how this stuff works again.. > > Krekna > > 2006/2/16, Krekna Mektek : > > Hi, > > > > Well, the dd_rescue did it's work, the array is now rebuilding, but > > it's doing its thing very slowly. > > > > But now the following, while the array is rebuilding and with the good > > image on my new disk (The FaultyRAIDDisk.img), I am trying to mount > > /dev/md0 already, but it now says : > > > > root@1[~]# fdisk -l /dev/md0 > > > > Disk /dev/md0: 800.1 GB, 800171491328 bytes > > 2 heads, 4 sectors/track, 195354368 cylinders > > Units = cylinders of 8 * 512 = 4096 bytes > > > > Disk /dev/md0 doesn't contain a valid partition table > > > > How can some individual disks which crash destroy my partition table!? Help! > > Is there some way to get my data back from here?? > > > > > > > > 2006/2/15, David Greaves : > > > man ddrescue: > > > -r, --max-retries= > > > exit after given retries (-1=infinity) [0] > > > > > > > > > So the -r10 basically tries to re-read each dodgy sector 10 times. > > > > > > Is it working? > > > > > > David > > > > > > Krekna Mektek wrote: > > > > > > >Hi, > > > > > > > >I am busy with it now, but what does the 10 mean in -r10 ? I > > > >understand from the --help that one can use the -r option, but without > > > >something behind it? > > > > > > > >Krekna > > > > > > > >2006/2/14, David Greaves : > > > > > > > > > > > >>Krekna Mektek wrote: > > > >> > > > >> > > > >> > > > >>>I want to rebuilt from the good one and the faulty one. That's why I > > > >>>wanted to dd the disk to an image file, but it complains it has no > > > >>>boot sector. > > > >>> > > > >>> > > > >>> > > > >>> > > > >>> > > > >>>>>>I did the folowing: > > > >>>>>> > > > >>>>>>dd conv=noerror if=dev/hdd1 of=/mnt/hdb1/Faulty-RAIDDisk.img > > > >>>>>>losetup /dev/loop0 /mnt/hdb1/Faulty-RAIDDisk.img > > > >>>>>> > > > >>>>>> > > > >>>>>> > > > >>>>>> > > > >>You could try doing this again using ddrescue (google if you need to > > > >>install it): > > > >> > > > >> ddrescue dev/hdd1 /mnt/hdb1/Faulty-RAIDDisk.img > > > >>/mnt/hdb1/Faulty-RAIDDisk.log > > > >> > > > >>Then do it again using -r10 (to increase the retries on the faulty sectors) > > > >> > > > >> ddrescue -r10 dev/hdd1 /mnt/hdb1/Faulty-RAIDDisk.img > > > >>/mnt/hdb1/Faulty-RAIDDisk.log > > > >> > > > >>This will be much quicker because the log file contains details of the > > > >>faulty sectors. > > > >>With luck (mucho luck) you may not even lose data. > > > >> > > > >>David > > > >> > > > >>-- > > > >> > > > >> > > > >> > > > >> > > > > > > > > > > > > > > > > > > > > > -- > > > > > > > > >