Re: backing up LVM volumes
Bernard <bdebreil@teaser.fr> wrote:
> When I stated that 'SystemRescueCD' did not backup LVM volumes,
> I meant that 'partimage' lacked this capability. As far as I know,
> recent versions cannot do any better.
I'm not familiar with partimage. Are you saying that it refuses to allow
you to backup partitions with names such as "/dev/vg/home" or
"/dev/mapper/vg-home"?
> I tried 'dd' again. It seems more promising, since it does backup
> everything. files are huge (about same size as the original partition,
> including empty space)
That's because it's a byte-for-byte copy.
> /mnt/sdc4/# dd if=/dev/sda1 of=sda1_04_10.img
Go back and read what I wrote about dd. You *really* ought to specify
a blocksize (for example, bs=100k).
> I must say that my original /dev/sda1 was my 'boot' partition. As such,
> the RAID/mdadm programs did not create a LVM system ; it kept using the
> original ext3.
You probably needed to have updated the disk partition table, too.
> /mnt/sdc4/# dd if=/dev/sda2 of=sda2_04_10.img
> /mnt/sdc4/# dd if=sda2_04_10.img of=/dev/sdc1
> I can't read, or even mount sdc1 :
> root@new-host:/home/bd# mount /dev/sdc1 /mnt/exthd
> mount: unknown filesystem type 'lvm2pv'
> root@new-host:/home/bd#
That suggests that sdc1 is a raw LVM partition, which you would not be
expected to mount as a filesystem. Are you SURE you're trying to dd from
a filesystem image and not from an underlying LVM segment?
It seems to me that you may be very confused (maybe you don't even know
it?!). If you want specific advice, please can I ask that you run these
commands (as root) and post the output.
for D in /dev/[hs]d[a-z]; do fdisk -l "$D"; done
mdadm -v --examine --scan
pvdisplay | grep Name
lvdisplay | grep Name
mount | grep ^/dev/
This will give us a view on what Disk/RAID/LVM/Filesystem combinations
you actually have.
Chris
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