BOOT(8)               NetBSD/x68k System Manager's Manual              BOOT(8)

NAME
     boot -- system bootstrapping procedures

DESCRIPTION
   Power fail and crash recovery
     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.

   Cold starts
     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 cur-
     rently supported.

   Bootstrapping from a floppy
     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 pro-
     gram 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.

   Bootstrapping from a SCSI hard disk
     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-indepen-
     dent IPL menu program at the top of the disk.  The IPL menu program rec-
     ognizes the partition table, and selects the partition to read the oper-
     ating system kernel.  During this phase, when the HELP key on the key-
     board 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 par-
     tition.

   Normal Operation
     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 exam-
     ple above, it will be ``sd0a:netbsd'' which is the file netbsd on parti-
     tion ``a'' of the NetBSD SCSI hard disk of ID 0.  Pressing a key within
     the time limit will enter interactive mode.

   Interactive mode
     In interactive mode, the boot loader will present a prompt, allowing
     input of these commands:

           boot [device:][filename] [-adqsv]
                  The default device will be set to the disk that the boot
                  loader was loaded from.  To boot from an alternate disk, the
                  full name of the device should be given at the prompt.
                  device is of the form xd[N[x]] where xd is the device from
                  which to boot, N is the unit number, and x is the partition
                  letter.

                  The following list of supported devices may vary from
                  installation to installation:

                  sd      SCSI disks on a controller recognized by the IOCS.
                          The unit number is the SCSI ID.
                  fd      Floppy drives as numbered by the IOCS.

                  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   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 ddb(4).

                  -q   Boot the system in quiet mode.

                  -s   Bring the system up in single-user mode.

                  -v   Boot the system in verbose mode.

           help   Print an overview about commands and arguments.

           ls [path]
                  Print a directory listing of path, containing inode number,
                  filename and file type.  path can contain a device specifi-
                  cation.

           halt   Reboot the system.

   Model-specific notes
     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.

FILES
     /netbsd               system code
     /netbsd.gz            gzip-compressed system code
     /usr/mdec/xxboot_ufs  boot block (read by installboot), xx is disktype
     /usr/mdec/boot        source of /boot (can be just copied to the root
                           directory)
     /boot                 main part of the boot program

SEE ALSO
     reboot(2), disklabel(8), halt(8), reboot(8), shutdown(8)

NetBSD 5.0_STABLE                April 8, 2003               NetBSD 5.0_STABLE
