Entering the Bootstrap Program
3
Hardware Installation Guide
C-3
Hardware User’s Guide
The following system bootstrap commands are among the most useful:
•
Boot—The b command with no argument reboots the system and boots the
default software from ROM as defined by the lower four bits of the
configuration register which form the boot field. You can include an argument,
filename, to specify a file to be booted over the network using the Trivial File
Transfer Protocol (TFTP). You can also include a second argument, host,
which is the Internet address or name of a particular server host. You must
enter the i command (explanation follows) and press Return before entering
b. The various forms of the b command follow:
-
b—Boots the default system software from ROM
-
b filename [host]—Netboots using TFTP
-
b flash—Boots the first file in Flash memory
-
b flash [filename]—Boots the file (filename) from Flash memory
To prevent the router from automatically netbooting or booting from anywhere,
enter the o/r 0x0 command.
•
Continue—The c command allows you to exit the bootstrap mode without
rebooting the router after you press the Break key while running the system
software image.
•
Help—The h command prints a summary of the bootstrap commands to the
console screen. This is the same output produced by entering ?.
•
Initialize—The i command causes the bootstrap program to reinitialize the
hardware, clear the contents of memory, and boot the system if so directed by
the boot field in the virtual configuration register. (It is best to use the i
command before running any tests or booting software.)
•
Display Stack Trace—The k command displays a stack trace of the last
running system software. This stack trace will be useful as a diagnostic
reading in the event of a problem such as an unexpected system crash.
•
Display/Reset Virtual Configuration Register—The o command displays the
virtual configuration register. The o command used with the /r option will
reset the configuration register and cause the system software image to ignore
the system configuration information in NVRAM (sets the ignore NVRAM
contents bit, 0x0040).
