text: **Note:**A controller that is connected through Fibre Channel is detected automatically by the 
  system. The cabling, the zoning, and the system layer must be configured correctly. A 
  controller that is connected through iSCSI must be added to the system manually. 
  
  Depending on the type of back-end system, it might be detected as one or more controller 
  objects. 
  
  If**External Storage**does not appear in**Pools**, virtualization licenses are not configured. To 
  use Storwize V7000 virtualization functions, you must order the correct External Virtualization 
  licenses. You can configure them by clicking**Settings**→**System**→**Licensed Functions**. 
  For assistance with licensing questions or to purchase any of these licenses, contact your 
  IBM account team or IBM Business Partner. 
  
  The**External Storage**pane lists the external controllers that are connected to the system 
  and all the external MDisks that are detected by the system. The MDisks are organized by the 
  external storage system that presents them. Toggle the sign to the left of the controller icon to 
  show or hide the MDisks that are associated with the controller. 
  
  If you configured logical unit names on your external storage systems, it is not possible for the 
  system to determine these names because they are local to the external storage system. 
  However, you can use the LU UID’s, or external storage system WWNNs and LU number, to 
  identify each device. 