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SuperTrak66™ User's Manual 
Chapter 3 
 
- 27 - 
Creating a RAID 5 Array 
Use the information in Chapter 6 to help determine the selection of a RAID 5 array.  
In the Definition Menu section, use the [Space] key to cycle through array types 
and select "RAID 5" for RAID Mode. You must configure such an array using a 
minimum of three drives because of parity data generation. 
 
You will be joining either two (if 3 drives are assigned) or three (if 4 drives are 
assigned) of the drives together and splitting (or striping) data written among them. 
Each member of such an array will no longer be readable as an independent drive if 
removed from the array. The capacity of the array will equal the capacity of the 
smallest drive multiplied by one less than the total number of drives assigned to the 
array. 
 
NOTE: If you choose to use just three drives, an unassigned fourth drive can be 
your "hot spare” drive in case of drive failure (see p. 28). 
Changing Stripe Block Size for RAID 5 Array 
For RAID 5 arrays, SuperTrak66 will allow you to change the stripe block 
size. The default is 64K. However, certain application environments may 
perform optimally with different values (see drive manufacturer for additional 
information on block sizes). To change the block size, use the arrow keys 
to highlight the field and the spacebar to cycle through the available size 
selections.  
NOTE: you can not change the block size AFTER the array has been 
created.
 
Assigning Drives to a RAID 5 Array 
Under the [ Drive Assignments ] section, highlight a drive, and, with the 
[Space] bar, change the Assignable option to “Y” to add the drive to the 
disk array. Press <Ctrl-Y> to save the disk array information. The initial 
Define Array Menu screen will appear after you have pressed [Ctrl-Y]. You 
will see the array defined. You may ESC to exit and return to the Main 
Menu of SuperBuild. 
 
Creating a Spanning Array 
In the [Define Array] section, use the [Space] key to cycle through array types and 
select "JBOD" for RAID Level. You will be joining the drives you assign  to this array 
together as a single "virtual" drive grouping. Data will be stored to the first drive until 
it is physically full. SuperTrak66 then will save data on to the next drive in 
sequence. Each member of an array will no longer be readable as an independent 
drive if removed from the array. The capacity of the Spanning array will equal the 
total capacity of all drives assigned.