The query is as follows :
A typical server configs when using Oracle or any other type of DB is to install the OS + DB binaries on the internal disks of the relevant server e.g.
Disk 1 : OS + SW + DB binaries
Disk 2 : Mirror of disk 1 (used for resiliency)
Then one uses an external array that is typically connected via Fibre Channel Card from Server to Storage Array.
One then configures the storage array either in RAID 10 or RAID 5 (typically a trade off between READ/WRITE speed vs. STORAGE DURATION/LENGTH).
Now the question is if one had a server which has the capacity of having 6 x Internal Disks (e.g. 6 x 146 GB 15K rpm SAS) what is the trade off if:
(1) Disk 1 = OS + SW + DB binaries
(2) Disk 2 = Mirror Disk 1 (e.g. RAID 1 config)
(3) Disk 3 & 4 are then RAID 10 to Disks 5 & 6 , where Disk 3 & 4 hold the raw vols for the DB
Would it still be better to use a Fibre Channel Card to an External Storage Array to house the raw vols of the DB and why ?