Which command is used to check the fan status of a device?

The command to check the fan status of a device is 'display fan.' This command is specifically designed to provide real-time information regarding the operational status of the fans within the device, including their speed and whether they are functioning correctly. Monitoring the fan status is crucial in maintaining optimal operating temperatures and ensuring the device does not overheat, which can lead to hardware failure or reduced performance.

Other commands such as 'display device' and 'display running-status' may provide general device information or overall system performance metrics, but they do not specifically focus on the fans. Similarly, 'display memory-usage' is aimed at memory consumption metrics and does not provide any indication related to fan functionality. Thus, 'display fan' is the most relevant command for assessing fan status.