CentOS virt - Feb 2010 - Mounting LVM contained ntfs systems.

Using CentOS 5.4 Xen Virtualization "stock install"

Added rpmforge NTFS extension for mount command.

Scenario: Have mirror dd'd off to "backup" unmounted LV contained 
Windows machine. Within the LVM volume are two NTFS partitions formatted 
by Win2k8.

Issue: How can I mount this? I need to verify file existence and run 
batch of file compare checks.

If I try to mount the LV:

~~~~~~~~~~~~~
[root at vm1 ~]# mount -t ntfs /dev/thisvg00/thisw2kwe-b4change /mnt/ntfs
NTFS signature is missing.
Failed to mount '/dev/mapper/serv1vg00-w2kwe--b4cert': Invalid argument
The device '/dev/mapper/serv1vg00-w2kwe--b4cert' doesn't seem to
have a
valid NTFS.
Maybe the wrong device is used? Or the whole disk instead of a
partition (e.g. /dev/sda, not /dev/sda1)? Or the other way around?
~~~~~~~~~~~~~

Would I have had an easier situation if I just had made one big C: 
partition instead of two (1 for OS and progs, other for data and 
applications)?

----- "Ben M." <centos at rivint.com> wrote:
> If I try to mount the LV:
> 
> ~~~~~~~~~~~~~
> [root at vm1 ~]# mount -t ntfs /dev/thisvg00/thisw2kwe-b4change
> /mnt/ntfs
> NTFS signature is missing.
> Failed to mount '/dev/mapper/serv1vg00-w2kwe--b4cert': Invalid
> argument
> The device '/dev/mapper/serv1vg00-w2kwe--b4cert' doesn't seem
to have
> a 
> valid NTFS.
> Maybe the wrong device is used? Or the whole disk instead of a
> partition (e.g. /dev/sda, not /dev/sda1)? Or the other way around?
Did you dd the disk or the partition? If you did the whole disk (verify with
fdisk or something), you can use kpartx to add the LV as a disk and then mount
the partitions that are created.

-- 
Christopher G. Stach II
http://ldsys.net/~cgs/

----- "Ben M." <centos at rivint.com> wrote:
> I dd'd the LV from a snapshot to an empty LV on a different VG with 
> identical extents like this:
> 
> dd if=/dev/vgsnapshotsource/win2k8-snapshot
> of=/dev/vgtarget/win2k8-target
> 
> I'm a little confused by what you mean by "partition" and
disk in this
> context. There is the LV container created, a partition, but also a 
> volume and presented as a "disk" to the Windows vm.
I meant from the perspective of Linux. It is unclear to me how many layers are
involved and whether or not you already did the kpartx bit, but if in case you
didn't... If Windows is using the LV as an entire disk and partitions it,
you have to use that partition table, too.

-- 
Christopher G. Stach II
http://ldsys.net/~cgs/