Compaq EK-SMCPO-UG. C01 manual RAID 0+1 Example, Drives Selected, Function

Models: EK-SMCPO-UG. C01

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2-16RAID Array 3000 Pedestal Storage Subsystem Hardware User’s Guide

Figure 2-6 shows a diagram of RAID 0+1 write.

Figure 2-6. Diagram of RAID 0+1 write

In the event of a drive failure, a RAID 0+1 array will enter degraded mode and continue to operate by substituting the failed drive with its mirror.

When the controller creates a RAID 0+1 set, it first sorts the drives by channel number and SCSI ID. Then it stripes the data across every other drive and forms a mirrored pair with the first two drives, another mirrored pair with the second two drives, and so on. Table 2–5 lists how the controller uses the drives in a RAID 0+1 set.

Table 2-5

RAID 0+1 Example

Drives Selected

Channel 1, ID 0

Channel 1, ID 1

Channel 1, ID 2

Channel 2, ID 0

Channel 2, ID 1

Channel 2, ID 2

Function

First member of stripe set

Mirror of channel 1, ID 0

Second member of stripe set

Mirror of channel 1, ID 2

Third member of stripe set

Mirror of channel 2, ID 1

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Compaq EK-SMCPO-UG. C01 manual RAID 0+1 Example, Drives Selected, Function