Connect the drive
First plug in the drive as normal and let Gnome/KDE mount the partitions it can see. My USB connected disk gets mounted to /media and is device /dev/sdb.
$ cd /media $ ls -l total 14 drwxr-xr-x 4 root root 1024 2007-12-05 07:10 _boot drwxr-xr-x 11 bobpeers root 4096 1970-01-01 01:00 DATA drwxrwxrwx 1 root root 8192 2007-10-19 23:00 SYSTEM
Here you can see the 3 mounted partitions
- _boot is my Linux boot partition
- DATA is my FAT32 partition
- SYSTEM is my main Windows NTFS partition
So no Linux partitions visible. To see what’s actually on the disk we can use fdisk as root.
# /sbin/fdisk -l /dev/sdb Disk /dev/sdb: 40.0 GB, 40007761920 bytes 255 heads, 63 sectors/track, 4864 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x86c986c9 Device Boot Start End Blocks Id System /dev/sdb1 * 1 1567 12586896 7 HPFS/NTFS /dev/sdb2 1568 2220 5245222+ c W95 FAT32 (LBA) /dev/sdb3 2221 2245 200812+ 83 Linux /dev/sdb4 2246 4864 21037117+ 5 Extended /dev/sdb5 2246 4864 21037086 8e Linux LVM
So we see that /dev/sda1 through 3 are mounted but /dev/sdb4 and 5 are the Logical Volume holding the Linux data I need to mount and copy to the new drive.
Scan the drive with pvscan
To see what logical volumes are available use the following command as root. The man page for pvscan says ‘pvscan scans all supported LVM block devices in the system for physical volumes’.
# /sbin/pvscan PV /dev/sdb5 VG Fedora_volume lvm2 [20.03 GB / 0 free] PV /dev/sda5 VG Linux_volume lvm2 [44.81 GB / 32.00 MB free] Total: 2 [64.84 GB] / in use: 2 [64.84 GB] / in no VG: 0 [0 ]
Here we can now see 2 logical volume groups, the first (Fedora_volume) is the one we want on /dev/sdb5 (the USB drive) while the second (Linux_volume) is the one on my new internal drive, /dev/sda5
Scan the drive with lvscan
We can also use lvscan to scan for logical volumes and to give more detail.
# /usr/sbin/lvscan inactive '/dev/Fedora_volume/LogVol00' [14.03 GB] inherit inactive '/dev/Fedora_volume/LogVol02' [5.00 GB] inherit inactive '/dev/Fedora_volume/LogVol01' [1.00 GB] inherit ACTIVE '/dev/Linux_volume/LogVol00' [33.78 GB] inherit ACTIVE '/dev/Linux_volume/LogVol02' [10.00 GB] inherit ACTIVE '/dev/Linux_volume/LogVol01' [1.00 GB] inherit
The reason why I can’t see the USB logical volume is now clear, it’s marked as inactive. Here we see 3 logical volumes in the Fedora_volume volume group. These are the 3 partitions I created: 1GB swap, 5GB Home and 14GB root.
Activate the Volume Group with lvchange
To activate the volume group is very simple.
# /usr/sbin/lvchange -a y /dev/Fedora_volume
Now the volume group is active I can create mount points and mount each partition within the volume group.
Mount the partitions as normal
# mkdir /mnt/root # mkdir /mnt/home
Note that I didn’t create a mount point for /dev/Fedora_volume/LogVol01 as this is my swap partition.
To mount the volumes is now simple.
# mount -t ext3 /dev/Fedora_volume/LogVol00 /mnt/root # mount -t ext3 /dev/Fedora_volume/LogVol02 /mnt/home
Now we can access all our data contained on the LV’s. When finished just unmount (umount) the partitions and mark the Volume Group as inactive.
# /usr/sbin/lvchange -a n /dev/Fedora_volume