content_image/1005546.jpg content_image/1005547.jpg
## DRAID Rebuild 

The spare area for rebuild on FS9100 is reserved against the physical capacity of the drives. As the rebuild progresses, the data is copied to the remaining drives, increasing the capacity threshold as shown in Figure 2-7. 

<img src='content_image/1005546.jpg'>

## DRAID copyback 

DRAID copyback is a similar process to the rebuild process. Upon completion, FS9100 releases the space area by UNMAP-ing the area that was used, as shown in Figure 2-8. 

<img src='content_image/1005547.jpg'>

