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I have an older dell power edge 6800 server. I have upgraded it a bit and I want to utilize it. So I wadded some ram and some drives.

it currently has 12 drives. 2 @ (146gb) 10 @ (300 gb)

I configured the first 2 drives RAID 1 "mirror" for the OS. And then 2 of the 10 drives are another RAID 1. Then the last 8 drives I want to configure them RAID 10. But the tool is only giving me 2 raid options 1 and 5 but not 10.

I am not sure why. Is there a limitation in the utility? If so, how can I fix that? What do I need in order to configure those 8 drives to Raid 10.

Thanks

Mike
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  • Which RAID configuration tool? For that matter, which RAID controller, and which version? – HopelessN00b Sep 05 '14 at 14:50
  • Hi, the bios configuration tool is "Bios Config utility is U827 jan 21, 2005" and the raid controller "H435 dated April 23 2008" and the raid. – Mike Sep 06 '14 at 01:06

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Alright, based on the sever model and the dates you gave in the comments, the RAID controller you have is a Perc 4/DC or Perc 4e/Di RAID card. They're pretty old, and accordingly, don't have the fancy automatic options you're accustomed to in newer software, like the automagical put-these-drives-in-RAID-10" configuration option, so you have to do it manually.

RAID 10 is a nested RAID level, which is to say it is a stripe of mirrors - groups of RAID 1 arrays that are then striped together into one larger array. In your case, if you want to put these 8 drives into a single RAID 10 array, you will need to first create 4 RAID 1 arrays, and then apply a RAID 0 array onto all four RAID 1 arrays.

To do this in your particular software, you would use the span option and select all four of the RAID 1 arrays you would have just created. From Dell's Perc 4 Easy Configuration guide:

PERC 4 supports spanning of RAID 1 and 5 arrays. You can span two or more contiguous RAID 1 logical drives into a RAID 10 array, and two or more contiguous RAID 5 logical drives into a RAID 50 array. You need at least two hard drives in two separate RAID 1 arrays to create a RAID 10 array and at least three hard drives in two separate RAID 5 arrays to create a RAID 50 array.

For two arrays to be spanned, they must have the same stripe width (they must contain the same number of physical drives) and must be consecutively numbered.

For example, assuming array 2 contains four hard drives, it can be spanned only with array 1 and/or array 3, and only if arrays 1 and 3 also contain four hard drives. If the two criteria for spanning are met, PERC 4 automatically allows spanning. If the criteria are not met, the Span setting makes no difference for the current logical drive.

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HopelessN00b
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  • Thank a lot for this answer. I am following your logic. As I am in the middle of trying to construct the RAID 10 manually as your suggestion. The only thing that I am not sure on how to do is how can I select all 4 spans "raid 1 spans" and make them a RAID 0. I don't see an option to allow me to do that. Do you know the step that I should follow? What I did is go to new configuration and then I selected 2 disks at a time and made them RAID 1 but now, I am stuck and I am not sure how to select the span itself to convert it to raid 0. do I initialize the drives first and then reconstruct again? – Mike Sep 08 '14 at 17:16
  • @Mike Unfortunately, I don't have access to a PERC 4 card, and my memory's foggy on exactly how it works, so I don't think I can be of any more assistance. :( Sorry. – HopelessN00b Sep 08 '14 at 18:28