In the HPE Aruba Networking Central monitoring framework, the platform maintains a persistent management connection (via WebSockets) to every managed AOS-CX switch.

The Connectivity Heartbeat: Central continuously monitors the status of this connection. If a switch loses power, its management processor stops functioning immediately. After a short timeout period where the heartbeat is not received, Central marks the device as " Down " and triggers the Switch Disconnected alert.

VSX Architecture in Central: It is important to note that even though two switches are in a VSX (Virtual Switching Extension) pair, Aruba Central treats them as individual managed entities for connectivity purposes. If the Primary switch goes offline, Central sees that specific device ' s management tunnel drop.

Evaluating Other Options:

Option A (Switch Reboot): A reboot alert is typically generated when a switch gracefully restarts or when it checks back into Central after an unexpected power cycle. If the switch remains powered off, it is simply " Disconnected. "

Option B (Switch Stack Conductor Change): This is a specific alert for VSF (Virtual Switching Framework) stacks (like the 6200 or 6300 series). In VSF, a failure of the master results in a role change. In VSX, there is no " Conductor " role; there is a Primary and Secondary, and they are not managed as a single " stack " object in the same way VSF is.

Option D (Switch STP Root Change): While a VSX Primary failure might trigger an STP re-election if that switch was the Root Bridge, the direct management alert from Central regarding the hardware state is " Switch Disconnected. "