Example:
In a typical data center installation, top-of-rack switches connect servers to the data network, while the management ports of those switches connect to a physically and logically separate management network. This allows network administrators to manage the switches even if operation on the data network is disrupted.
In the figure below, the switches face the hot aisle of the data center, allowing easy connection to the network ports on the backs of the servers.
For even more control, the serial console ports of the switches can be connected to the management network through a serial console server (essentially, a networked serial switch), allowing the network administrators to view the CLI activity of each switch at boot time and to control the switches through the console ports (as well as through the management ports).