Cisco Systems 2600 manual Configuration Register Commands

Appendix B Using the ROM Monitor

ROM Monitor Command Descriptions

•sysret—Views return information from the last booted system image. This information includes the reason for terminating the image, a stack dump of up to eight frames, and, if an exception is involved, the address where the exception occurred. For example:

rommon 8> sysret

System Return Info:

count: 19, reason: a SegV exception

pc:0x802b1040,	error address: 0x802b1040
Stack Trace:
FP: 0x80908398,	PC: 0x802b102c
FP: 0x809083b0,	PC: 0x802b0b88
FP: 0x809083d8,	PC: 0x8017039c
FP: 0x809083e8,	PC: 0x8016f764

Configuration Register Commands

The configuration register resides in NVRAM. You can view or modify the configuration register from either the ROM monitor or the operating system software.

For procedures used to change the configuration register from the operating system, and for information about configuration register settings, see Appendix C, “Configuration Register.”

To modify the configuration register from the ROM monitor, you can:

•Enter the confreg command by itself for menu mode. See the “Modifying the Configuration Register in Menu Mode” section below.

•Enter the confreg command plus the new hexidecimal value of the configuration register. See the “Modifying the Configuration Register by Hexidecimal Entry” section on page B-8.

In either case, the new configuration register value is written into NVRAM, but is not effective until you reboot (using the ROM monitor reset command) or power cycle the router.

Modifying the Configuration Register in Menu Mode

Entering the confreg command without an argument displays the contents of the configuration register, and prompts you to alter the contents by describing the meaning of each bit.

The following display shows an example of the confreg command:

rommon	7> confreg
Configuration Summary
enabled	are:
break/abort has effect
console	baud: 9600
boot: the ROM Monitor
do you	wish to change the configuration? y/n			[n]: y
enable	“diagnostic mode”? y/n	[n]:	y
enable	“use net in IP bcast address”? y/n			[n]:
enable	“load rom after netboot fails”? y/n			[n]:
enable	“use all zero broadcast”? y/n		[n]:
disable	“break/abort has effect”? y/n		[n]:
enable	“ignore system config info”?		y/n [n]:
change	console baud rate? y/n	[n]:	y
enter rate: 0 = 9600, 1 = 4800, 2 = 1200,				3 = 2400
	4 = 19200, 5 = 38400, 6 = 57600, 7 = 115200 [0]: 0
change	the boot characteristics? y/n		[n]:	y
			Cisco 2600 Series Routers Hardware Installation Guide
OL-2171-06					B-7