Drives are now in the  Candidate  state, as shown in Figure 5-18. A managed disk (MDisk) is a logical unit (LU) of physical storage. MDisks are either arrays  (RAID) from internal storage or LUs that are exported from external storage systems. Storage  pools act as a container for MDisks by dividing the MDisks into extents. Storage pools  provision the available capacity from the extents to volumes. 132  IBM FlashSystem 9100 Architecture, Performance, and Implementation 5.4.3 Working with and creating storage pools Figure 5-18 Drives Use set to Candidate 5. Select  Pools MDisks by Pools  to view the drives that are available for creation of  MDisks and Storage Pools, as shown in Figure 5-19. Figure 5-19 Select Pools MDisks by Pools