IBM 81Y Computer Hardware User Manual


 
120 Hardware Maintenance Manual: xSeries 250
Create an array using the two physical drives.
Then, create a logical drive within that array.
The data is striped across the drives, creating blocks. Notice that the data on the drive
on the right is a mirror copy of the drive on the left.
With RAID level-1, if one of the physical drives fails, the ServeRAID controller
switches read and write requests to the remaining functional drive in the RAID level-
1 array.
Understanding RAID Level-1 Enhanced
If you have three or more physical drives in the array, you can no longer select RAID
level-1, but you can select RAID level-1 Enhanced (also called RAID level-1E).
RAID level-1E combines mirroring with data striping. This RAID level stripes data
and copies of the data across all of the drives in the array. As with the standard RAID
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