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Install and maintain

Maintain AFF A900 hardware

Contributors netapp-martyh dougthomp netapp-jsnyder

For the AFF A900 storage system, you can perform maintenance procedures on the following components.

Boot media

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.


The DCPM (destage controller power module) contains the NVRAM11 battery.


The fan cools the controller.

I/O module

The I/O module (Input/Output module) is a hardware component that acts as an intermediary between the controller and various devices or systems that need to exchange data with the controller.


The LED USB module provides connectivity to console ports and system status.


The NVRAM module (Non-Volatile Random Access Memory) allows the controller to retain data across power cycles or system reboots.

Power supply

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

Real-time clock battery

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