RAID questions (was Re: [TriLUG] Re: Dieing hard drive?)

[Tanner Lovelace]

On Tue, 30 Nov 2004 13:18:00 -0500, Aaron S. Joyner <aaron at joyner.ws> wrote:
> First sentence, untrue.  The proper way to state this would be that most
> on-board IDE controllers are not capable of hot swapping drives.  And
> since most boxen these days use the on-board controller, most internally
> mounted IDE drives can not be swapped.  On the other hand, most on-board
> RAID controllers, or almost all PCI RAID controllers, are capable of
> swapping in and out drives.  Most can even disconnect one drive on a
> channel, while leaving the other drive on the channel sufficiently
> intact.  I have done this numerous times in the BSD world, with generic
> PC hardware, so I know the hardware is capable of it.  It's been a while
> since I've done it in the Linux world, so I can't describe the process
> off the top of my head, but I imagine there are folks on the list who
> can.  In the case of internal drives used for backups, you're often
> going to need to add a controller -- make it a $20 IDE RAID controller,
> and you can easily swap in and out the disks.  Even if they're in a
> drive enclosure which is attached to said controller.  :)

While we're talking about RAID what version of RAID would people 
suggest?  A couple of weeks ago I had my 160GB /home drive
die on me and I'm thinking of replacing it with a RAID setup.  The 
idea here isn't to replace regular backups, but rather to make it
so that I'm not completely screwed if a drive decides to die on me.
Should I go with two large drives and mirror it or would it be
better to get 3 slightly smaller drives and do something like RAID 5?
What are the advantages/disadvantages of each setup?

Also, should I consider getting a "$20 IDE RAID controller" or just
use software RAID?

Thanks.

Cheers,
Tanner