Usually after RAID/LUNs configuration, people usually don't move drives around. However, in some cases, you may need move drives from one channel to the others. MegaRAID SAS Controller has Drive roaming that allows you to move drives from channel to others without worrying data lost.
Drive roaming occurs when the drives are changed to different ports on the same controller. When the drives are
placed on different channels, the controller detects the RAID configuration from the configuration data on the drives.

Configuration data is saved in both the NVSRAM on the RAID controller and on the drives attached to the controller. This action maintains the integrity of the data on each drive, even if the drives have changed their physical device ID.

NOTE: If you move a drive that is being rebuilt, the rebuild operation restarts; it does not resume from the stopping point.
Follow these steps to use the drive roaming feature:

1.Power off server

Turn off the power to the server and all drives, enclosures, and system components. Disconnect the power cords from the system.

2.Open the host system

Open the host system by following the instructions in the host system technical documentation.

3.Move drives

Move the drives to different positions on the backplane to change the targets.

4.Determine the SAS target requirements.

5.Perform a safety check.

     a. Make sure that the drives are inserted correctly.
     b. Close the cabinet of the host system.

6. Reconnect the power cords to the system.
7. Turn on the power to the system.

The controller then detects the RAID configuration from the configuration data on the drives.