Open Boot is the boot loader progran for Sparcs
This means disk partition a on scsi disk at target 3, logical unit 0 on the esp device at slot 0, offset 40000 which is connected to sbus (system bus) at slot 1 offset f8000000
To save having to type full device paths, aliases can be used. For the most common devices these are already defined, e.g.cdrom. The command devalias is used to define aliases.
- devalias - displays all current aliases
- devalias alias - shows device associated with alias specified
- devalias alias device-path - define an alias
Note: Aliases defined by devalias are temporary and are lost after a power cycle or system reset. Use nvalias to create alias permanent (see below).
Device trees can be shown with Unix like commands e.g. ls, pwd, cd .show-devs shows all devices from the current level down.
format: boot device-specifier filename options
- device-specifier - e.g. cdrom, disk, floppy, net, tape . Note:These are aliases and vary from system to system
- filename - e.g. /stand/diag
- options - -a (interactive) -h (halt) -r (reset)
- probe-scsi - identify all devices attached to the built in scsi bus
- probe-scsi-all - as probe-scsi but ALL scsi buses
- test device-specifier - perform self test on device e.g. test cdrom , test /memory , test net
- test-all - test all devices that have a built in self test
- watch-clock - test click function
- watch-net - monitor network connections
- .enet-addr - display current ethernet address
- .version - show version of boot PROM
NVRAM contains the system configuration parameters which control machine start up configuration and communications characteristics
- printenv - show the parameters
- setenv parameter value - changes a parameter e.g. setenv diag-switch? true enables extra diagnostics, setenv boot net sets the boot device, setenv auto-boot? false sets the server not to boot automatically
Access to the open boot commands can be limited using the security parameters. i.e. setting security-mode to none , command or full . command mode requires a password for some functions, full is also known as restricted mode and requires a password for most functions. It also enables restricted monitor format, i.e. a menu.
This is a portion of nvram reserved for user commands.
Changing NVRAMRC contents
- nvalias alias device_path - store command devalias alias device_path in NVRAMRC
- nvedit - edit contents of NVRAMRC in a temporary buffer. Special key strokes are required, normally in format CONTROL_letter
- nvquit - quit editing without saving
- nvrecover - recover contents of NVRAMRC
- nvrun - execute contents of temporary buffer (if using nvedit)
- nvunalias - delete saved alias