However, if you are managing a Dell PowerEdge server or a system utilizing a Broadcom/LSI MegaRAID controller, you have likely encountered a frustrating roadblock. When attempting to check drive health with a standard command like smartctl -a /dev/sda , you are met with a cryptic error message:
The most common mistake is guessing the N value. You cannot use 0, 1, 2 blindly. You must map the physical disks. However, if you are managing a Dell PowerEdge
From the operating system's perspective, it sees a single block device (e.g., /dev/sda ). It has no idea that /dev/sda is actually a RAID 5 array consisting of four physical spinning disks. The OS speaks to the controller, and the controller manages the physical drives. However, if you are managing a Dell PowerEdge