- Introduction
- Booting a System
- The OpenBoot Environment
- The OpenBoot Architecture
- The OpenBoot Interface
- Getting Help in OpenBoot
- PROM Device Tree (Full Device Pathnames)
- OpenBoot NVRAM
- OpenBoot Security
- OpenBoot Diagnostics
- OpenBoot PROM Versions
- Booting a System
- The Kernel
- The init Phase
- System Shutdown
- Summary
- Suggested Readings and Resources
Getting Help in OpenBoot
At any time, you can obtain help on the various Forth commands supported in OpenBoot by using the help command. The help commands from the ok prompt are listed in Table 3.2.
Table 3.2 OpenBoot help Commands
Command |
Description |
help |
Displays instructions for using the help system and lists the available help categories. |
help <category> |
Shows help for all commands in the category. You use only the first word of the category description. |
help <command> |
Shows help for an individual command. |
Because of the large number of commands, help is available only for commands that are used frequently.
The following example shows the help command with no arguments:
ok help
The system responds with the following:
Enter ‘help command-name’ or ‘help category-name’ for more help (Use ONLY the first word of a category description) Examples: help system -or- help nvramrc Categories: boot (Load and execute a program) nvramrc (Store user defined commands) system configuration variables (NVRAM variables) command line editing editor (nvramrc editor) resume execution devaliases (Device Aliases) diag (Diagnostic commands) ioredirect (I/O redirection commands) misc (Miscellaneous commands) ok
If you want to see the help messages for all commands in the category diag, for example, you type the following:
ok help diag
The system responds with this:
test <device> Run the selftest method for specified device test-all Execute test for all devices with selftest method watch-net Monitor network connection probe-scsi Show attached SCSI devices ok ok help misc
The system responds with this:
reset-all Reset system (similar to a power-cycle) power-off Power off system sync Reenter operating system to sync the disks eject-floppy Eject floppy from drive ok ok help boot
The system responds with this:
boot [<device-specifier>:<device-arguments>] [boot-arguments] Examples: boot Default boot (values specified in NVRAM variables) boot disk1:h Boot from disk1 partition h boot myunix -as Boot from default device. Pass boot program "myunix -as" Booting from network boot <network-device>:[dhcp,][server-ip],[boot-filename],[client-ip], [router-ip],[boot-retries],[tftp-retries],[subnet-mask] [boot-arguments] ok