NAME

boot − loader for any stand-alone program. 

DESCRIPTION

This section contains information related to the stand alone utilities available in the /stand directory.  These utilities are used to format/verify new drives, copy from tape to disk or from disk to disk, and install the root file system during installation procedures.  The most well known stand-alone programs are boot, cat, vdformat, format, fastcopy, ls, vdupdate and unix.  DEVICE NAMES:

The stand alone utilities have a set of names for devices which are different from the names that unix uses.  Currently, the stand alone utilities only support disk and tape devices.  The disk and tape names used by the stand alone utilities are:

generic disks    dsk
generic tapes    mt
 

The stand-alone boot, used to bootstrap the full CX/UX system, uses device names of the form: xxx[(a[,b[,c[,d]]])] where xxx is either dsk or mt.  For all controllers except HDC dsk’s, the a value specifies which controller to use.  The default value is 0.  For HDC’s, a is a VME slot number. The default is 2.  The b value specifies which drive on the controller to use.  The default value is 0.  The c value specifies which partition to use.  Disk partitions are numbered from 0 through 7.  For mag tape devices this is the starting file number.  The default value is 0.  The d value specifies which bus to use. The default value is 0.  There may be either one or two I/O buses on a CX/UX system.  The bus which contains the Console Processor is considered to be the primary bus - bus number 0.  If the other bus is present, it is considered to be the secondary bus - bus number 1.  RUNNING BOOT:

All the utilities are loaded by the boot program which is started in the mode which asks the user which file to load. After each execution the utility restarts from the beginning waiting for new arguments from the user. To execute another utility the boot has to be restarted. 

The boot program loads /unix on the default boot disk by default.  The cp monitor command (p23) affects the operation of boot, unix and init. 

Each bit in p23 specifies an option for the boot program, unix or init.  The values assigned to p23 and their meanings are as follows:

p23 1.        (boot) Asks user to specify the program to load. 

p23 2.        (init) Boots /unix to single user mode. 

∗p23 20.      (init) Reset system console. 

p23 40.      (unix) Ask for partition to boot from. (generic option)

∗p23 80.      (unix) Debug option. (Load UNIX symbol table into memory)

p23 100.    (boot and unix) Load program and halt before executing. 

p23 400.    (unix and init) Mount root filesystem writable and don’t execute
           /etc/rc.boot. 

Multiple options may be set in one command by or’ing the option bits.  For example, p23 3 asks the user to specify the program to load and then boots to single user mode. 

Options flagged with an ∗ are retained across a system reboot unless specifically reset. 

CX/UX Administrator’s Reference