Changing Configuration Register Settings
Table C-1
Bit
Number
10
5, 11, 12 0x0020,
13
14
15
Changing Configuration Register Settings
You might want to modify the value in the configuration register to perform the following tasks:
•
•
•
•
•
You can change the configuration register either from the ROM monitor or from the operating system
software. To change the configuration register from the ROM monitor, see the
section on page
following steps:
Connect a console terminal to the console port of the router as described in the
Step 1
Console Port" section on page
Note
For information about cable pinouts, see the publication
Specifications
Configure your terminal or terminal emulation software for 9600 bps (default), 8 data bits, no parity, and
Step 2
2 stop bits.
Power up the router.
Step 3
When asked if you would like to enter the initial dialog, answer no:
Step 4
Would you like to enter the initial dialog? [yes]: no
Your router is now in the normal operating mode.
Cisco 3700 Series Routers Hardware Installation Guide
C-2
Configuration Bit Meanings (continued)
Hexadecimal
Meaning
0x0400
IP broadcast with all zeros.
Console line speed.
0x0800, 0x1000
0x2000
Boots default ROM software if the network boot fails.
0x4000
IP broadcasts do not have net numbers.
0x8000
Enables diagnostic messages and ignores the contents of NVRAM.
Recover a lost password.
Change the console data rate.
Enable or disable the Break function.
Manually boot the operating system using the b command at the ROM monitor prompt.
Force the router to automatically boot its system image in CompactFlash memory, or boot in
accordance with any boot system commands stored in the router's configuration file in NVRAM.
B-6. To change the configuration register from the system software, perform the
If you have a terminal with a DB-25 port, use an RJ-45 rollover cable and DB-25 adapter. The
RJ-45-to-DB-25 adapter (Cisco part number 29-0810-01) can be purchased from Cisco.
on Cisco.com.
3-22, using the blue RJ-45 to DB-9 console adapter cable.
Cisco Modular Access Router Cable
Appendix C
Configuration Register
"Configuration Register"
"Connecting to the
OL-2180-08