In a computer network, a master computer has an operating system (OS) management table for mapping unique addresses of the network computers to respective versions of an operating system and a status table for mapping the unique addresses to respective busy/idle states of the computers and to respective queues. A list of the OS versions is retrieved from the management table to allow user at a source computer to select one of the versions, and a request is sent to the master computer. In response, the master computer makes a search through the management table for remote computers in which the operating system of the selected version is installed and makes a search through the status table to determine their busy/idle states and to detect one of their queues having shortest length if all of the remote computers are busy. The request from the source computer is stored into the shortest length queue and a network boot command signal is sent from the master computer to the remote computer of the shortest length queue when it receives therefrom a network boot complete message upon completion of a network boot process on an older request in the shortest length queue. The remote computer of the shortest queue length responds to eachp network boot command signal by transmitting a copy of the selected version of the operating system to the source computer.