The boot media stores a primary and secondary set of boot image files that the system uses when it boots.

The chassis is the physical enclosure housing all the controller components such as the controller/CPU unit, power supply, and I/O.

A controller consists of a board, firmware, and software. It controls the drives and implements the ONTAP functions.

You must replace a DIMM (dual in-line memory module) when a memory mismatch is present, or you have a failed DIMM.

A drive is a device that provides the physical storage media for data.

The fan cools the controller.

The NVDIMM (non-volatile dual in-line memory module) manages the data transfer from the volatile memory to the non-volatile storage, and maintains data integrity in the event of a power loss or system shutdown.

A NVDIMM battery is responsible for maintaining power to the NVDIMM module.

A PCIe (peripheral component interconnect express) card is an expansion card that plugs into the PCIe slot on the motherboard.

A power supply provides a redundant power source in a controller shelf.

A real time clock battery preserves system date and time information if the power is off.