C-6
Cisco Secure Router 520 Series Software Configuration Guide
OL-14210-01
Appendix C ROM Monitor
Configuration Register
Changing the Configuration Register Manually
To change the virtual configuration register from the ROM monitor manually, enter the confreg
command followed by the new value of the register in hexadecimal format, as shown in the following
example:
rommon 1 > confreg 0x2101
You must reset or power cycle for new config to take effect
rommon 2 >
The value is always interpreted as hexadecimal. The new virtual configuration register value is written
into NVRAM but does not take effect until you reset or reboot the router.
Changing the Configuration Register Using Prompts
Entering the confreg command without an argument displays the contents of the virtual configuration
register and a prompt to alter the contents by describing the meaning of each bit.
In either case, the new virtual configuration register value is written into NVRAM but does not take
effect until you reset or reboot the router.
The following display shows an example of entering the confreg command:
rommon 7> confreg
Configuration Summary
enabled are:
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]:
enable “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 [0]: 0
change the boot characteristics? y/n [n]: y
enter to boot:
0 = ROM Monitor
1 = the boot helper image
2-15 = boot system
[0]: 0
Configuration Summary
enabled are:
diagnostic mode
console baud: 9600
boot: the ROM Monitor
do you wish to change the configuration? y/n [n]:
You must reset or power cycle for new config to take effect