questions about RAID 0

[diluzio91]

if i have a 320 gb seagate, do i have to get the same drive to be able to raid? or could i get like a WD 320 to use with it? I appreciate your help TBCS!

[x88x]

1) What are you using to manage the array (hardware controller, software, etc).
2) Usually, no, as long as the capacity is the same it doesn't matter.

[diluzio91]

im just planning on using my motherboard's built in controller to manage it. im getting a small SSD for my OS, and want to put my games on a raid 0 with the 320's. then have a 1t for storage and backups

[BuzzKillington]

Even if the capacities are different, the raid will just limit the larger drive to the same size as the smaller one.

[x88x]

Sounds like a good plan. ..just make sure you back up any data you would mind losing onto that 1TB...if a drive dies in a RAID 0 you're hosed. :(

[Konrad]

Semi-related query:

The RAID will limit the larger drive to match the smaller drive's capacity. Can the extra space be allocated to another partition for other use?

[mDust]

Semi-related query:

The RAID will limit the larger drive to match the smaller drive's capacity. Can the extra space be allocated to another partition for other use?

I'm not sure, but it would slow your array down anytime the larger drive had to seek something on the spare partition. If it is possible it wouldn't be worth it.

The RAID 0 array will generally be 1.5-1.9x faster than the slowest drive. So for these reasons and those posted above, identical drives are recommended.

[Konrad]

I always feel bad wasting space. Still can't bear to throw away all those gigabytes of ATA66/100/133. I was actually thinking of a recovery partition which could boot the software tools needed to rebuild a broken RAID array ... obviously wouldn't see a lot of use, but damned nice to have handy when you need it.

I've never tried it; my RAIDs have always been matched pairs (or sets) of identical drives.

[Kayin]

I would recommend identical drives for that reason. If I'm buying a set for RAID, they're all the same drive, ordered at the same time.

[mDust]

I always feel bad wasting space. Still can't bear to throw away all those gigabytes of ATA66/100/133. I was actually thinking of a recovery partition which could boot the software tools needed to rebuild a broken RAID array ... obviously wouldn't see a lot of use, but damned nice to have handy when you need it.

I've never tried it; my RAIDs have always been always pairs (or sets) of identical drives.

Thinking about how it would all work now, I'm pretty sure the array would just disregard the wasted space and that would be that. The OS wouldn't see any leftover space because it's looking at the array, not at the drive. If the array broke you wouldn't be able to access either drive anyway, so keeping the tools to fix the broken drive on the broken drive wouldn't end well.
My arrays have always used identical drives as well. I know dissimilar drives work without trying it myself, but various things happen that are not optimal.

[x88x]

If I'm buying a set for RAID, they're all the same drive, ordered at the same time.
Very rarely you might run into a problem with this.. A friend of mine who's a tech/admin at a web hosting company was building up a few large storage arrays for a client a few years ago and it just so happened that all of the Seagate Cheetahs that he was using were all from a run that had a bad supply of controller chips..~10 minutes after turning it on, the entire array went up in smoke (literally). :facepalm:


Thinking about how it would all work now, I'm pretty sure the array would just disregard the wasted space and that would be that.
It depends how you're doing the array. For example, on my fileserver I just use mdadm software RAID, addressing partitions, not physical drives. If you do that, you could easily have a separate partition for the rest of the drive. But, like you said, if that drive fails it wouldn't help you anyway...

[Konrad]

Oh, ick. Software RAID? What's the point?

[x88x]

Oh, ick. Software RAID? What's the point?

Cheap.
Flexible.
Durable (If all my controllers, my MBB, my CPU, and my OS HDD..well, OS CF in this case.. all fail, I just drop the drives in another Linux system and tell it to find the array).
Controller agnostic.
Easy multi-controller array.
Performance doesn't really matter in this implementation (simple storage, always accessed over 1Gbps ethernet, lower RPM low-power drives).
Oh, and did I mention cheap? :P

[Konrad]

Hmmm. Worth thinking about.