Accessing a partition that uses LVM-on-RAID from Ubuntu LiveCD
The Ubuntu Live CD does not come with LVM or the MD administration tools, so if your existing system uses LVM and/or MD (the linux software RAID functionality), the partitions are not visible by default within the LiveCD. To get access to your data, pull up a terminal (Applications menu → Accessories → Terminal) and switch to root:
ubuntu@ubuntu:~$ sudo -i root@ubuntu:~#
Start by installing the software needed (since its a live CD, this just installs to the temporary in-memory “RAM disk”):
root@ubuntu:~# apt-get install lvm2 mdadm
With that completed, you can assemble your existing array(s):
root@ubuntu:~# mdadm --assemble --scan mdadm: /dev/md0 has been started with 2 drives.
Then scan for the LVM physical volumes:
root@ubuntu:~# pvscan PV /dev/md1 VG nathan lvm2 [465.52 GB / 0 free] Total: 1 [465.52 GB] / in use: 1 [465.52 GB] / in no VG: 0 [0 ]
Activate the logical volumes contained within:
root@ubuntu:~# vgchange -a y 3 logical volume(s) in volume group "nathan" now active
And finally, mount whichever partition you were interested in:
root@ubuntu:~# mount /dev/nathan/data /mnt