Configuration of Raid

[richard.pieri-Re5JQEeQqe8AvxtiuMwx3w at public.gmane.org (Richard Pieri)]

On May 11, 2010, at 1:41 PM, Dave Peters wrote:
> 
> We have a MD3000i (15 x 450GB 15K rpm) and MD1000 (15 x 1TB 7.2 RPM) joined together. How many Raid Group and LUN should I create for the best performance? 15K RPM disk will be used for Database Server and 7.2 RPM disk group will be used as Web Server?
> Any suggestion?

Maximum spindle distribution = maximum performance (usually), so glom the 15x450GB into a single striped set (RAID 0) and the 15x1TB into a single striped set (also RAID 0).  Your reliability will suck.  Each stripe set has 15 points of failure with zero redundancy.

For redundancy and performance, I would set up 14 disks from each set in a RAID 1+0 with 1 hot spare.

Although... I have to wonder... why do you have 15TB of disk for your web server but "only" 7TB for your database?

--Rich P.