[SOLVED] about software raid

qrange · 03-02-2011, 05:23 AM

I got two harddisks, sda and sdb. Is it possible to install Debian root into software raid partitions sda2 and sdb1 leaving all other partitions 'normal' (not-raid)?

do partitions sda2 and sdb1 need to be exact same size and position?

crts · 03-02-2011, 05:51 AM

Hi,

from the manpage:

Quote:

Normally when an array is built the "size" it taken from the smallest of the drives.

As for the 'normal' other partitions it should be no problem.
However, you will have to use a separate, normal /boot partition.

Here is some more info on raid:
http://tldp.org/HOWTO/Software-RAID-HOWTO.html

qrange · 03-02-2011, 06:10 AM

thanks, I got another question. would it be possible to move existing Debian installation into raid?
(for eg. sda2 has 100% Debian root, I'd like it to move 50% to sdb1)

brian-va · 03-02-2011, 04:50 PM

You may be able to use the dd command to copy it over, but like crts said you would need a separate /boot partition.
Just be careful, the dd command is powerful and can end up bitting you (data loss).
Might be easier to just reinstall; creating the array during the install isn't too difficult.

jlinkels · 03-02-2011, 06:27 PM

Quote:

Originally Posted by qrange

thanks, I got another question. would it be possible to move existing Debian installation into raid?
(for eg. sda2 has 100% Debian root, I'd like it to move 50% to sdb1)

This is a step-by-step instruction for an existing Debian installation to RAID:
http://www200.pair.com/mecham/raid/r...aded-etch.html

You are free as which partitions to RAID or not. A RAIDed partition is accessed an md[0-n] whereas a non-RAIDed partion is simply sda[1-n] or so. In Debian (and perhaps others) booting from RAID1 is perfectly safe. The RAID driver is included in initrd.

jlinkels