RAID Level SQL Server Configuration

[lcolson1959]

We are wanting to increase performance on 1 of our SQL Server's. Right now we have two RAID 5 Arrays. OS and Logs on one and the Data Files; including tempdb on the other. Our other server has RAID 1+0 across 3 separate RAIDS. The only thing that is throwing me is that I thought you needed a minimum of 4 drives for RAID 1+0. Each of the three RAID 1+0 arrays have only 2 drives??

I would not think our protection level is very good with only 2 drives. Granted 1 drive can fail with a catastrophe.

For the server we are wanting to increase performance I am suggesting RAID 1 for the OS & Logs Files that would include 2 drives. RAID 1+0 with 4 drives for the Data files. RAID 1+0 with 2 drives for TempDB. Have I maximized fault tolerance as well as performance with this thought process?

lcolson1959

MCSA, MCDBA, MCTS (SQL 2005), A+, N+, DHTI+

 

[JayKusch]

Here is a little blurb I pulled from the net that may explain what you are seeing with your current RAID 10.

To answer how many disk drives are needed for RAID 10: This depends on the storage array vendor's firmware.

RAID 10 configurations can be accomplished by mirroring a stripe set, or striping a mirror set.

When you stripe a mirror set, you first create two mirror sets and then create a stripe set from the two mirrors (minimum four drives).

When you mirror a stripe set, you first create two stripe sets (usually of at least three drives each) and then mirror them to another stripe set (total of six drives).

Thanks

J. Kusch

 

[lcolson1959]

That is pretty much what I pulled off the net. I am surprised that I have only 2 drives in each of the RAID 1+0 arrays. How is this possible. From the blurb I should have a minimum of 4. So how can it be RAID 1+0 with only 2?

lcolson1959

MCSA, MCDBA, MCTS (SQL 2005), A+, N+, DHTI+

 

[mrdenny]

A RAID 1+0 which has two drives is actually a RAID 1 array. A RAUD 1+0, 0+1, or 10 requires 4 drives. There must also be an even number of drives.

Denny
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