AIX - Logical Partitioning - I/O device assignment

Aix - Logical Partitioning - I/O device assignment

• I/O devices are assigned to partition profiles on a slot-by-slot basis. Most I/O devices can be assigned to a partition profile on the HMC as required or as desired.
• If an I/O device is assigned to a partition profile as required, then the partition profile cannot be successfully activated if the I/O device is unavailable or is in use by another logical partition. Also, after the logical partition starts, you cannot use dynamic logical partitioning to remove the required I/O device from the running logical partition or move the required I/O device to another logical partition. This setting is suitable for devices that are required for the continuous operation of the logical partition (such as disk drives).
• If an I/O device is assigned to a partition profile as desired, then the partition profile can be successfully activated if the I/O device is unavailable or is in use by another logical partition. The desired I/O device can also be reconfigured in the operating system or system software and removed from the running logical partition or moved to another logical partition using dynamic logical partitioning. This setting is suitable for devices that you want to share among
  multiple logical partitions (such as optical drives or tape drives). You can change the required or desired setting within any partition profile for any I/O device at any time. Changes to the required or desired setting for an I/O device take effect immediately, even if the logical partition is running. For example, you want to move a tape device from one running logical partition to
  another, and the I/O device is required in the active partition profile for the source logical partition. You can access the active partition profile for the source logical partition, set the tape device to be desired, and then reconfigure and move the tape device to the other logical partition without having to restart either logical partition.