Appendix D: Understanding RAID 167

RAID 10 Logical Drives

A RAID 10 logical drive is built from two or more equal-sized RAID 1

logical drives. Adaptec RAID controllers support a maximum number

of 48 disk drives in a RAID 10 logical drive.

Data in a RAID 10 logical drive is both striped and mirrored. M irroring

provides data protection, and striping improves performance.

Drive segment size is limited to the size of the smallest disk drive in the

logical drive. For instance, a logical drive with two 250 GB disk drives

and two 400 GB disk drives can create two mirrored drive segments of

250 GB, for a total of 500 GB for the logical driv e, as shown below.

Disk Drive 1
Disk Drive 2
Disk Drive 3
Disk Drive 4
250 GB
250 GB
400 GB
400 GB
D
isk Drives in Logical Drive
Disk Drive 1
Disk Drive 2
Disk Drive 3
Disk Drive 4
RAID 10 Logical Drive = 500 GB
1
2
1
2
Not Used
Not Used
3
4
3
4500
499
500
499
...
...
...
...
Unused Space: 150 G
B
Unused Space: 150 G
B
Drive Segment Size (Smallest Disk Drive)