-a
Prompt for the root file system device, the system crash dump device, and the path to
init(8).
-d
Bring the system up in debug mode. Here it waits for a kernel debugger connect; see
gdb(1).
-C
Boot kernel in compat mode. Starting with revision 1.14 (introduced on 2003/03/01), the sparc boot program loads the NetBSD kernel at its linked virtual address. This feature requires a kernel built after 2003/02/21 (corresponding to kernel version 1.6Q). To load older kernels, the -C option must be used, which loads the kernel at physical address 0x4000. The size of a kernel loaded in this way is limited to approximately 3MB.
-q
Boot the system in quiet mode.
-s
Bring the system up in single-user mode.
-v
Boot the system in verbose mode.
Any extra flags or arguments, or the <
boot string> after the -- separator are passed to the boot PROM. Other flags are currently ignored.
The SPARC boot ROM comes in two flavours: an “old-style” ROM is used in sun4 machines, while a “new-style” ROM can be found on sun4c and sun4m models. The “new-style” SPARC boot ROM is a full-featured Forth system with emacs key bindings. It can be put in “old-style” user-interface compatibility mode (in which case it shows a simple ‘>' prompt), but this is essentially useless. However, by default on sun4c models, the ROM runs in old-mode; to enter new-mode type ‘n'. The ROM then shows a Forth-style “ok” prompt. It is recommended to have the ROM always start in its native “new-style” mode. Utter the following incantation in new-mode to force the ROM to always start in new-mode.
ok setenv sunmon-compat? false
The ROM will normally load the kernel from “sd(0,0,0)vmunix”. To change the default so that
NetBSD will be loaded from somewhere else, type the following
ok setenv boot-from sd(0,0,0)netbsd
On newer SPARC machines, there are various aliases to access common devices. A typical list of usable boot devices (extracted from the output of the Open Boot PROM command
devalias) is:
floppy /obio/SUNW,fdtwo
net-aui /iommu/sbus/ledma@f,400010:aui/le@f,c00000
net-tpe /iommu/sbus/ledma@f,400010:tpe/le@f,c00000
net /iommu/sbus/ledma@f,400010/le@f,c00000
disk /iommu/sbus/espdma@f,400000/esp@f,800000/sd@3,0
cdrom /iommu/sbus/espdma@f,400000/esp@f,800000/sd@6,0:d
tape /iommu/sbus/espdma@f,400000/esp@f,800000/st@4,0
tape1 /iommu/sbus/espdma@f,400000/esp@f,800000/st@5,0
tape0 /iommu/sbus/espdma@f,400000/esp@f,800000/st@4,0
disk3 /iommu/sbus/espdma@f,400000/esp@f,800000/sd@3,0
disk2 /iommu/sbus/espdma@f,400000/esp@f,800000/sd@2,0
disk1 /iommu/sbus/espdma@f,400000/esp@f,800000/sd@1,0
disk0 /iommu/sbus/espdma@f,400000/esp@f,800000/sd@0,0
For new-style machines, if a device specification includes a partition letter (for example
cdrom in above list), that partition is used by default, otherwise the first (a) partition is used. If booting from the net device, there is no partition involved.
At any time you can break back to the ROM by pressing the ‘L1' and ‘a' keys at the same time (if the console is a serial port the same is achieved by sending a ‘break'). If you do this accidentally you can continue whatever was in progress by typing ‘go'.