Settinng up a mirrored raid with 2 80 gig HDs

This is my first time setting up an xServe. I know I need to set-up a mirrored raid with my 2 80 gig drives, but I also read that I should not place my other software on the same partition as the OS incase I need to ever perform a clean install. My question is do I need to purchase a 3rd drive module, or can I set-up a partition within the mirrored raid scenario? If so, how do I do this with the Disk Utility?
Dual 2.3GHz PowerPC G5 Mac OS X (10.4) Running Tiger Server

Dan Soderholm-
I don't think partitioning a RAID is bad in some situations as long as you are aware of the pitfalls.
First would be speed. If one partition held data and one held applications, the heads of the drive have to scramble between partitions in order to grab all of the data. This slows things down significantly in practice.
The second major problem is data loss. If something fails, you are losing more than one "drive" and must deal with the associated hassles of rebuilding everything. If you have a robust backup strategy you can mitigate the negative effects of this however.
Your theory bout getting into trouble and wiping the system partition can be another false sense of security. Nine times out of ten when something goes south you will be wiping the entire disk and starting from scratch, and usually after you have spent considerable time just trying to wipe the system partition. It always seems to be the partition information that gets wrecked.
Luck-
-DaddyPaycheck

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https://discussions.apple.com/message/25119317#25119317
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Well I'm sure VERY few people have multiples of EVERYTHING. I still have my data.
All I want to do is mirror a fresh drive with the other drive that was part of a mirrored raid set. That should be possible... it seems...
Please don't admonish me for not having more backups. I have a total of 1.25 terabytes of HD space with a lot of redundancy.

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is it possible (and how) to get rid of the RAID and convert one of the discs to a normal startup volume so i can reformat the second disc and use it as a work drive ? Since the 'mirrored' drives both contaion a full startup drive this should be possible i think but could not find any info on this.
thx for any help with this ...

hey .. funny how expert opinions vary ... i have a handfull of IT and software RAID experts who disagree with you ... in my case, i'd rather get rid of it ... ( however i still have to find a solution to clone my boot drive that works flawlessly with all my software ... )
anyways ... how exactly do i go about splitting the RAID, to make sure i don't mess it up ....
1. restart from CD
2. Delete the mirrored RAID set
3. remove one of the HDs with the raid slice on it (i'll keep it as a backup 4 the moment just in case)
4. restart from the remaining slice disc
5. ... ?
do i need to do anything specific ... ? what about the name of the Volume .. for the moment my startup disk (the RAID) is called 'BootRAID' ... the slices are called 'RAID Slice (disk0s2)' and 'RAID Slice (disk1s2)' .. in order for everything to work properly, don't i have to rename the new startup disk ?
i'm scared ...
here's a screenshot of my setup: http://kinkajou.net/diskUtility_RAID.jpg
<Edited by Moderator>

Settinng up a mirrored raid with 2 80 gig HDs

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