questions re: moving to a RAID config

[Jonathan Hudson]

On Tue, 23 Dec 2008 11:19:30 -0600, bill walton wrote:

>Greetings!  And apologies in advance if this is deemed to be off topic.
>I'm looking for info and how-to links.
>
>Background:
>System is a 8.04 64-bit Ubuntu workstation install hosting VMware.  The
>box currently has (I think) a single 500GB drive installed which is set
>up as two 250GB partitions; one has Ubuntu/VMware installed on it and
>the other is empty.  I want to move to a RAID configuration using two
>(new) 500GB drives.
>
>Questions:
>1) Is there much chance of doing this other than via a fresh install of
>everything?
>
>2) Given that the hardware supports RAID, is there any advantage of
>using a software raid solution?
>

1. In principle quite easy.

* backup your data

* Create the raids on the new drives 

* copy the old stuff over

* set grub to boot of the new drives

Actually, you only need one new drive, as you could set the raid up
with one missing drive, then when it's booted, add the old disk into
the raid. If you only room for two drives in the machine at once, then
you'd do this anyway:

* remove empty 250MB drive, install one new new 500MB
*  configure new drive as raid1 with missing device
* copy all old stuff over
* set up grub to boot new drive

* boot new drive, when satisfied it's all working, remove old drive,
  add in the other new one, create duplicate partitions and add to raid.
* Stand back in wonder as the raid syncs.

2. Yes, you can do stuff like the above. 

-jh