A method and system. A first computer device sends to a second computer device, via a broadcast or multicast communication, an event notification of a notifiable management event, The first computer device may connect to a management network via only a first network switch, wherein the first computer device is unable to notify a management device of the notifiable management event via the management network because the first computer device is unable to connect to the management network via the first network switch. The first computer device receives, from the second computer device via a first unicast communication, an acknowledgment of the event notification, wherein the second computer device is able to connect to the management network via the second network switch. The broadcast or multicast communication and the first unicast communication each use a short-range wireless communications technology comprising visible light communication or data-over-audio communication.