Dell SCSI 6/IR manual Example of Integrated Mirroring RAID

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, it does not matter if one of the disks fails. 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 1-3. Example of Integrated Mirroring (RAID 1)

Stripe element 1 Stripe element 2 Stripe element 3 Stripe element 4

Stripe element 1 Duplicated Stripe element 2 Duplicated Stripe element 3 Duplicated Stripe element 4 Duplicated

Overview

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