Dell Serial Attached SCSI 6iR Integrated and Adapter - Manual (Page 15)

Overview
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Figure 2-2. Example of Integrated Striping (RAID 0)
Integrated Mirroring
With Integrated Mirroring (RAID 1), data written to one disk is
simultaneously written to another disk. If one disk fails, the contents of the
other disk can be used to run the system and rebuild the failed physical disk.
The primary advantage of Integrated Mirroring is that it provides 100 percent
data redundancy. Because the contents of the disk are completely written to a
second disk, the system can sustain the failure of one disk. Both disks contain
the same data at all times. Either physical disk can act as the operational
physical disk.
NOTE:
Mirrored physical disks improve read performance by read load balance.
Figure 2-3. Example of Integrated Mirroring (RAID 1)
stripe element 1
stripe element 5
stripe element 9 stripe element 2
stripe element 6
stripe element 10
stripe element 3
stripe element 7
stripe element 11
stripe element 4
stripe element 8
stripe element 12
stripe element 1
stripe element 2
stripe element 3 stripe element 1 duplicated
stripe element 2 duplicated
stripe element 3 duplicated
stripe element 4 stripe element 4 duplicated
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