Re: RAID 5 inaccessible - continued

[Krekna Mektek <krekna@gmail.com>]

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 <krekna@gmail.com>:
> 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 <david@dgreaves.com>:
> > man ddrescue:
> >       -r, --max-retries=<n>
> >               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 <david@dgreaves.com>:
> > >
> > >
> > >>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
> > >>
> > >>--
> > >>
> > >>
> > >>
> > >>
> > >
> > >
> > >
> >
> >
> > --
> >
> >
>