Diskless node

A Diskless Workstation is a personal computer without any means of non-volatile storage (hence 'diskless').

In order to boot such a PC, the Operating System (OS) 'image' has to be provided from some external store - typically across a network link (from a 'Server'), although other means of providing the OS image, such as from removable storage (such as a USB Pen drive) would also qualify, as would directly running a bootable CD containing an OS (such as Knoppix).

Needless to say, at least some parts of the OS have to be loaded directly into the PC's memory, part of which is configured as a RAM Disk. Bootstrapping such a PC usually involves a 2 step process, in which a RAM Disk is created, DOS is loaded and then the OS image is fetched and loaded into the RAM disk.

Any applications that the user might wish to use also have to be installed (i.e. loaded alongside the OS image).

After loading the OS, control has to be passed from the 'bootstrap' program to the OS itself. This is all but impossible with modern Microsoft Operating Systems (such as NT, 2000) so historically Diskless PC's have been limited to UNIX or LINUX based systems (although Windows 98se has also been used with some success).

The major advantage of a Diskless PC is that any system changes made during operation (due to user action, worms, virus, etc) are wiped out when the power is removed. This allows use in public access areas (such as Libraries) or in Schools etc. where users might wish to experiment or attempt to 'hack' the system.

This is also the major disadvantage - all work has to be saved to some external store (such as a Network Share or USB Pen drive etc).