Ubuntu's performance : how to speed up ?

[Bob Nielsen]

On Thu, Feb 17, 2005 at 06:40:06PM +0100, Vincent Trouilliez wrote:
> > And also twice the risk, right? If one of the disks go bad in a RAID-0
> > setup, you lose all the data. 
> 
> I did think of this. But to be fair, I would think it's safer ! You have
> two drives to hold your data, so if one fails, you lose only half of the
> data, whereas with only one disk holding the system, when it goes,
> everything is lost, the system is down, and the user data are lost as
> well, 100% disaster. One a big server with dozens of SCSI drives in
> array 5, when a disk fails, it's not the end of the world.
> But the problem is I think irrelevant. The point is, you should make
> regular back-ups of your system (or /home at least !). So if the disk
> "subsystem" (whatever it's constituted of) fails, you can recover the
> data from the backup. Granted, having multiple disks to hold the system
> is as secure (or unsecure) as relying on a single disk.
> 

I am not familiar with RAID arrays.  Is there a simple method to have
two disks where one automatically mirrors the content of the other,
which would protect all of the data if one of the drives were to fail?  
I realize that one could use a crontab to back things up on a regular 
basis, but wondered if there was a raid method for this.

Bob