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Restore LVM disk from image, made by dd

I hav LVM:

Code:

#lvs

  LV      VG        Attr  LSize  Origin Snap%  Move Log Copy%  Convert

  LogVol00 VolGroup01 -wi-a- 145.03g

  LogVol01 VolGroup01 -wi-a-  3.91g

And backup of LogVol00, that was made like this:

Code:

dd if=/dev/mapper/VolGroup01-LogVol00 bs=64K | gzip -c | > /mnt/usb/backup.img.gz

when i try to:

Code:

gunzip -c /mnt/usb/mapper_VolGroup01-LogVol00.img.gz | dd of=/dev/mapper/VolGroup01-LogVol00 conv=sync,noerror bs=64K

there is no errors, but when i try to mount recovered partition, i see an error:

Code:

# mount /dev/mapper/VolGroup01-LogVol00 /mnt-user/00/

mount: wrong fs type, bad option, bad superblock on /dev/mapper/VolGroup01-LogVol00,

missing codepage or helper program, or other error

In some cases useful info is found in syslog - try

dmesg | tail or so

I need that partition alive. Please, help me with it.

Did you find anything useful in syslog or check dmesg output as suggested when the mount failed?
When I tried this and checked dmesg output it reports: EXT3-fs: no journal found.
(You did not specify what filesystem was on your .img.gz so I went with ext3.)

Edit 1:
UPDATE:
FAILURE:

Code:

dd if=/dev/VolGroup01/LogVol00 bs=64K | gzip -c > /mnt/usb/backup.img.gz



gzip -d -c /mnt/usb/backup.img.gz | dd of=/dev/VolGroup01/LogVol00 conv=sync,noerror bs=64K



mount /dev/VolGroup01/LogVol00 /mnt-user/00/

SUCCESS

Code:

dd if=/dev/VolGroup01/LogVol00 bs=64K | gzip -c > /mnt/usb/backup.img.gz



gzip -d -c /mnt/usb/backup.img.gz > /mnt/usb/backup.img



dd if=/mnt/usb/backup.img of=/dev/VolGroup01/LogVol00 conv=sync,noerror bs=64K



mount /dev/VolGroup01/LogVol00 /mnt-user/00/

Not sure why decompressing first and then using dd on decompressed .img to place it on the LV works while the decompression to stdout and pipe to dd fails, but worth a shot to see if it works for you if you have the ~145.03g free somewhere to stage it.

Edit 2:

OK, the bs=64K seems to be what is breaking it for me. When I use bs=512, while it takes substantially longer, I do not get 'No space left on device' and I am able to successfully mount the filesystem on it.

That looks suspiciously like you are over-writing a lv on a running system ... :eek:
I'm thinking you'll need to rescan those (LVM) devices - search here on LQ for pvscan and vgscan (and vgchange).

Try this first:

Code:

gunzip -c /mnt/usb/mapper_VolGroup01-LogVol00.img.gz | dd of=/dev/mapper/VolGroup01-LogVol00 conv=sync,noerror bs=512

If that does not work and you have the space to stage the dd img somewhere before writing it to /dev/VolGroup01/LogVol01, try the steps in my previous post under "SUCCESS".

A have a lot of place for decompress images on /mnt/usb. The problem should be in dd-ing worked system drive. I have to made a snapshot if i want to backup without freezing my server, but i did not.