User manual
FastTrak TX2000™ Series User Manual 
48 
Under RAID 0+1, the array maintains data integrity if any 1, 2 combination survives. 
Event Failed Drives  Array Status  Why? 
1 A1/A2  Working   B1/B2 retain array integrity 
2 B2/B1  Working  A1/A2 retain array integrity 
3 A1/B2  Working  B1/A2 retain array integrity 
4 B1/A2  Working  A1/B2 retain array integrity 
5  A1/B1    Offline    B2/A2 contain only half of array data 
6  B2/A2    Offline    A1/B1 contain only half of array data 
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. 










