If the - a flag is supplied, or no flags are supplied, all interfaces will be used. The array at the end of the message contains information about the users logged in to the sending machine. Messages received by the rwho server are discarded unless they originated at an rwho server's port. Status messages are generated approximately once every 3 minutes. There should be a way to relay status information between networks.
People often interpret the server dying or network communtication failures as a machine going down.