Cisco 7000 Series Hardware Installation And Maintenance Manual page 176

Installing and Configuring Processor Modules
Caution
register settings might be combinations of settings and not just the individual settings listed in
Table 5-4. For example, the factory default value of 0x0101 is a combination of settings.
Table 5-4
Bit No.
00 to 03
06
07
08
09
10
11 to 12
13
14
15
1. The factory default value for the configuration register is 0x0101. This value is a combination of the
following: bit 8 = 0x0100 and bits 00 through 03 = 0x0001 (see Table 5-5).
2. OEM = original equipment manufacturer.
Table 5-5
Boot Field
00
01
02 to 0F
Changing Settings
Some common reasons to modify the value of the software configuration register are as follows:
•
•
•
•
•
To change the configuration register while running the system software, follow these steps:
Step 1
5-18 Cisco 7010 Hardware Installation and Maintenance
To avoid confusion and possibly halting the router, remember that valid configuration
Software Configuration Register Bit Meanings
1
Hexadecimal
0x0000 to 0x000F
0x0040
0x0080
0x0100
0x0200
0x0400
0x0800 to 0x1000
0x2000
0x4000
0x8000
Explanation of Boot Field (Configuration Register Bits 00 to 03)
Meaning
Stays at the system bootstrap prompt
Boots system image in system ROM
Specifies a default netboot filename
Enables boot system commands that override the default netboot filename
Recover a lost password.
Change the console baud rate.
Enable or disable Break.
Allow you to manually boot the operating system using the b command at the bootstrap program
(ROM monitor) prompt.
Force the router to boot automatically from the system bootstrap software (boot ROM image) or
from its system image in Flash memory, and read any boot system commands that are stored in
the configuration file in NVRAM. If the router finds no boot system commands, it uses the
configuration register value to form a filename from which to netboot a default system image
stored on a network server. (See Table 5-6.)
Enter the enable command and your password to enter privileged level, as follows:
Meaning
Boot field (see Table 5-5)
Causes system software to ignore NVRAM contents
2
OEM bit enabled
Break disabled
Use secondary bootstrap
Internet Protocol (IP) broadcast with all zeros
Console line speed (default is 9,600 baud)
Boot default ROM software if network boot fails
IP broadcasts do not have network numbers
Enable diagnostic messages and ignore NVRAM contents