System Initialization (Sparc)

At boot time, a SPARC system will load the OpenBoot firmware, which then initializes basic hardware (such as the framebuffer, serial ports, keyboard, and disks), tests system functioning, and, optionally, (if the auto-boot? option is set to true) loads a primary bootloader in some way. Otherwise, it gives the user an "ok" prompt, at which to type initialization commands or FORTH instructions.

In theory, one could load an operating system from any device they wish, regardless of whether the device is directly supported by OpenBoot (eg, by typing in FORTH words to stick the raw bytes of the operating system code in memory). In parctice, however, an operating system is generally loaded from the hard disk, a floppy, or the network.

Hard disk

Typing "boot disk" at the boot prompt loads a bootloader from the hard disk, starting with sector 1 (512 bytes from the beginning of the disk) and continuing for 15 more sectors (7.5 Kb), assuming that the disk has a proper Sun Disklabel on it. Alternatively, "load disk" loads the bootloader into memory but does not load it.

Floppy

Somebody who has tried this, please fill this in. Theoretically, because disk-label provides the load command, it should work the same way, but who knows?

Network

Somebody who has tried this, please fill this in.