BOOT(8) | System Manager's Manual (x68k) | BOOT(8) |
boot
— system
bootstrapping procedures
Normally, the system will reboot itself at power-up or after crashes. An automatic consistency check of the file systems will be performed, and unless this fails, the system will resume multi-user operations.
The X68000/X68030 system boots from the device which is determined by the configuration of battery-backuped SRAM. By default, the boot ROM attempts to boot from floppy disk drives (from 0 to 3) first, and then attempts to boot from hard disk (SASI or SCSI). On the NetBSD/x68k, booting from SCSI disks (sd??) and 2HD floppy disks (fd?a, fd?c) is currently supported.
When the floppy disk is selected as the boot device, the initial program loader of the IOCS (firmware) reads the fdboot_ufs program at the top of the disk, and then the fdboot_ufs program loads the /boot program from the FFS or LFS file system. Normally, the /boot program then loads the NetBSD kernel /netbsd from the same floppy. In addition, the /boot program has abilities to uncompress gzip'ed kernels, to read the kernel from other disks of other file systems etc (see below).
For floppy disks, fdboot_ustar is also provided to read large kernels which do not fit one a single floppy.
When a SCSI hard disk is selected as the boot device, the initial program loader on the SCSI host adapter's ROM reads the operating system-independent IPL menu program at the top of the disk. The IPL menu program recognizes the partition table, and selects the partition to read the operating system kernel. During this phase, when the HELP key on the keyboard is pressed, the IPL menu program displays the partition menu of that disk to prompt the user to select the boot partition (although the NetBSD implementation of the IPL menu, /usr/mdec/mboot, does not have this functionality).
Next, the IPL menu reads the OS-dependent boot program from the top of the selected partition. For NetBSD FFS/LFS file systems sdboot_ufs is used. The sdboot_ufs program then loads the /boot program from that partition.
Once running, a banner similar to the following will appear:
NetBSD Multi-boot, Revision 1.1 (user@buildhost, builddate) Press return to boot now, any other key for boot menu booting sd0a:netbsd - starting in 5
After a countdown, the system image listed will be loaded. (In the
example above, it will be
“sd0a:netbsd
” which is the file
netbsd
on partition “a” of the
NetBSD SCSI hard disk of ID 0. Pressing a key within
the time limit will enter interactive mode.
In interactive mode, the boot loader will present a prompt, allowing input of these commands:
boot
[device:][filename]
[-adqsv
]The following list of supported devices may vary from installation to installation:
The default filename is netbsd; if the boot loader fails to successfully open that image, it then tries netbsd.gz (expected to be a kernel image compressed by gzip(1)). Alternate system images can be loaded by just specifying the name of the image.
Options are:
-a
-d
-q
-s
-v
help
ls
[path]halt
Note for X68030+MC68030 systems: Nothing special to be attended to; you can boot NetBSD just like as other operating systems such as Human68k and OS-9.
Note for X68030/040turbo(68040 accelerator by BEEPs) systems: NetBSD can boot under 040 mode. It can also boot under 030 mode if you have MC68030 on the board.
Note for X68000/Xellent30(68030 accelerator by TSR)+MC68030 systems: In order to boot NetBSD, you must choose 030 mode by using CH30.SYS, which must reside in the battery-backuped SRAM.
Note for X68000/Jupiter-X(68040/060 accelerator by FTZ-net) systems: The system must be in 040/060 processor mode.
August 16, 2014 | NetBSD 10.99 |