This error typically occurs when smartctl is unable to directly access the disk drive /dev/sda due to the presence of a RAID controller, specifically a Dell or MegaRAID controller.
megacli -ldinfo -lall This command will display information about all logical drives configured on the MegaRAID controller. Look for the logical drive number associated with the disk drive you want to monitor. This error typically occurs when smartctl is unable
To resolve this issue, you need to inform smartctl about the presence of the MegaRAID controller and the logical drive number (N) associated with the disk drive you want to monitor. You can do this by adding the -d megaraid,N option to the smartctl command. N option to the smartctl command.