Promise Technology FastTrak TX2000 User Manual page 52

Under RAID 0+1, the array maintains data integrity if any 1, 2 combination survives.
Event Failed Drives
1 A1/A2
2 B2/B1
3 A1/B2
4 B1/A2
5 A1/B1
6 B2/A2
Spanning (JBOD)
A Spanning disk array (also aptly named as JBOD for "Just a Bunch of Drives") is equal to the
sum of all drives when the drives used are of different capacities. Spanning stores data on to a
drive until it is full, then proceeds to store files onto the next drive in the array. There are no
additional performance or fault tolerance array features in this array. When any disk member
fails, the failure affects the entire array.
FastTrak TX2000™ Series User Manual
Array Status
Working
Working
Working
Working
Offline
Offline
Why?
B1/B2 retain array integrity
A1/A2 retain array integrity
B1/A2 retain array integrity
A1/B2 retain array integrity
B2/A2 contain only half of array data
A1/B1 contain only half of array data
48