How to detect RAID 0 from Ubuntu Live CD?

Question

I have Ubuntu 10.04 installed on a server with RAID 0 configuration. The server has many user accounts and the users have a lot of data in the server. The server has been crashed due to removal of certain packages and now there is kernel panic during startup.

How do I now take backup of the data present in RAID 0? Can I use a Ubuntu Live CD? Will it be able to detect the RAID 0? What do I need to do for the detection of RAID 0 from Ubuntu Live CD? I do not want to lose the data.

Is there a way to install Ubuntu without losing any data. Is there any other way to take back of all the data present in RAID 0?

Solution

I am not familiar with Ubuntu but there is no reason to assume that an Ubuntu live CD/DVD has problems with MD softRAID. You should see the MD devices with cat /proc/mdstat.

If they are not automatically recognized then you can create them with

mdadm --assemble /dev/md0 /dev/sda15 /dev/sdb15

Use fdisk -l /dev/sda or parted /dev/sda print (or vgdisplay -v) to find out what your MD base volumes are.

You can then mount /dev/md0 and access the data on it in the usual way.

Furthermore it should not be a problem to (re)install Ubuntu without touching the data on the RAID volume. Just don't touch it. Linux installers use just the volumes you tell them to use. If the OS itself is installed on a MD volume together with data you still need then have it installed without creating a filesystem (formatting) first.

Comments

[phemmer]

Have you tried booting up the live CD yet? If not, I suggest doing so, and then coming back if that doesn't work.

[New to Rails]

Thanks Patrick. I created Ubuntu 14.04 LTS Live CD and the raid 0 was detected and all the files are accessible from Live CD.

[New to Rails]

Thanks Hauke. I created Ubuntu 14.04 LTS Live CD and the raid 0 was detected and all the files are accessible from Live CD.