OS on raid or on seperate hard drive?

csmaster2005

Senior member
Nov 13, 2005
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So, I have 4 300gig HD's I want to setup in a raid-5. (Seagate 7200.10's). Technically I got 2 300 gig and 2 320 gigs.

I am trying to decide what would be better. Should I create the raid-5 array with the 4 hd's and then install the OS on that? Or should I install the OS on a seperate older 160gig WD hd, and then just store all I can on the array instead? If anyone can provide any input, that'd be great.


If it helps, the OS will be Windows Vista
I will use the onboard raid on my GA-p35 mobo

Another note: If I do go with the seperate drive for just Vista, it would be an IDE drive. The 4 300+ gig hd's are SATA

On a side note, anyone know if I can create 2 new partitions with the 320 gig hds, so I can use the extra 20 gigs, since the raid will only use 300 gigs?
thanks
 

MagnusTheBrewer

IN MEMORIAM
Jun 19, 2004
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Don't put your OS on a raid setup. Due to distributed parity, degradation can be substantial after a failure and during rebuilding.
 

csmaster2005

Senior member
Nov 13, 2005
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why should I go with raid-6? It would be extremely rare for 2 hd's to fail at once... and if that happens, then hell I'm just out of luck and deserve it.
If one of my HD's fail, I'd replace it ASAP to avoid another failure.

But IMO it isnt worth the loss in space to do raid-6 instead of raid-5
 

Fullmetal Chocobo

Moderator<br>Distributed Computing
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May 13, 2003
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Originally posted by: csmaster2005
why should I go with raid-6? It would be extremely rare for 2 hd's to fail at once... and if that happens, then hell I'm just out of luck and deserve it.
If one of my HD's fail, I'd replace it ASAP to avoid another failure.

But IMO it isnt worth the loss in space to do raid-6 instead of raid-5

I don't think he was being serious. Not to mention the performance hit on your mobo-based RAID controller. What is it about RAID 5 that requires you to need something better?
 

Snooper

Senior member
Oct 10, 1999
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I can say that I have my OS (and a LOT of other stuff!) on a 5 disk RAID5. I originally did it as a test. My day job included administering a NetApp filer and I wanted to play around with RAID5 at home..

But I also have to say that on the NetApp, while we have huge RAID5 arrays for data, the OS partition sits on it's own 3 disk RAID1 (aka: mirror). It takes a LOT to take one of these things down...

I have been in the rebuilding drive mode and it DOES impact your performance quite a bit. Of course, in my case, I just ignored the computer for a few hours and let it finish rebuilding the new drive. Some folks here have a hard time NOT using there computer constantly while they are awake, so if you are in that category, it might be best to avoid RAID5... I haven't found it to be an issue.

One other thing, you might want to try and put your swap file on a non RAID disk as well. Getting the swap file off the OS disk(s) is always a good idea and you don't need to back it up as the OS can rebuild it if there is a problem.
 

Madwand1

Diamond Member
Jan 23, 2006
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Keeping the OS on a separate drive / array from the main array is often a good idea because it greatly simplifies installation, configuration and maintenance.
 

Blain

Lifer
Oct 9, 1999
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"<a target=_blank class=ftalternatingbarlinklarge href="http://www.pcguide.com/ref/hdd/perf/raid/levels/singleLevel6-c.html">RAID 6 can be thought of as "RAID 5, but more". It stripes blocks of data and parity across an array of drives like RAID 5, except that it calculates two sets of parity information for each parcel of data.

The goal of this duplication is solely to improve fault tolerance; RAID 6 can handle the failure of any two drives in the array while other single RAID levels can handle at most one fault.</a>"

"Fault Tolerance: Very good to excellent. Can tolerate the simultaneous loss of any two drives in the array."

"Special Considerations: Requires special implementation; not widely available."