To fix this, you must use the -d megaraid,N flag to "pass through" the RAID controller and address a specific physical disk ID (N). 1. Identify the Correct Device ID (N) The number

For production servers, manually checking smartctl on each physical disk is tedious. Consider:

The error message suggests that the disk drive is behind a RAID controller, which is a hardware component that manages multiple disk drives as a single logical unit. In this case, the controller is a Dell or MegaRAID device. The smartctl utility needs to communicate with the disk drive through this controller, but it doesn't know how to do so by default.

Here's an example: