What is a cable management arm (CMA) used for?

• A. Hinged arm that manages cables when sliding a server out on rails.
• B. A backplane for NVMe drives.
• C. An airflow baffle.
• D. A mounting bracket for a chassis.

Answer: (A)

Cable management arms are designed to guide and protect the bundle of cables that connect a server to its power, network, and other connections, especially as the server is moved in and out on rails. The hinged or articulating arm stays attached to the server tray and follows the unit when you pull it out for maintenance, keeping cables neatly arranged and preventing strain, snagging, or unplugging traps during service. This ensures reliable connectivity and makes servicing quicker without tugging on individual cables.

The other options describe different components: a backplane for NVMe drives handles drive connectivity, an airflow baffle shapes or blocks airflow, and a mounting bracket for a chassis is a structural support. None of those functions center on managing cables during movement, which is the core purpose of a cable management arm.