Home » Cisco Manuals » Bridges & Routers » Cisco 3725 » Manual Viewer

Cisco 3725 Hardware Installation Guide - Page 105

Configuring the Boot Field

UPC - 746320810911

Add to My Manuals
Save this manual to your list of manuals

Page 105 highlights

Appendix C Configuration Register Configuring the Boot Field Step 5 Step 6 Step 7 After a few seconds, you see the user EXEC prompt (Router>). Enter the enable command and your password to enter privileged EXEC mode: Router> enable Password: password Router# At the privileged EXEC prompt (Router#), enter the configure terminal command: Router# configure terminal Enter configuration commands, one per line. Edit with DELETE, CTRL/W, and CTRL/U; end with CTRL/Z Enter the config-register value command, where value is a hexadecimal number preceded by 0x (see Table C-2), to set the contents of the configuration register: Router(config)# config-register 0x value Note Cisco IOS software does not allow you to change the console speed bits directly with the config-register command. To change the console speed, complete this sequence: Router# configure terminal Router(config)# line console 0 Router(config-line)# speed 9600 Step 8 Step 9 Press Ctrl-Z to exit configuration mode. Copy the new console speed to NVRAM: Router# copy run start Step 10 The new settings are saved to NVRAM, but they are not effective until the router restarts; for example, when you switch the power off and on or when you enter a reload command from the console. Enter the show version command to display the configuration register value currently in effect and the value that will be used at the next reload. The value is shown on the last line of the display: Configuration register is 0x142 (will be 0x142 at next reload) Step 11 Reboot the router. The new value is effective after the router reboots. Configuring the Boot Field The lowest four bits of the configuration register (bits 3, 2, 1, and 0) form the boot field. (See Table C-2.) Table C-2 Explanation of Boot Field Configuration Register Bits (00 to 03) Boot Field 00 01 02-F Meaning Stays at the ROM monitor on a reload or power cycle. Boots the first image in CompactFlash memory as a system image. Enables default booting from CompactFlash memory. Enables boot system commands that override default booting from CompactFlash memory. OL-2180-08 Cisco 3700 Series Routers Hardware Installation Guide C-3

Section	Page
Cisco 3700 Series Routers Hardware Installation Guide	1
Contents	3
Preface	7
Objectives	7
Audience	8
Organization	8
Conventions	8
Safety Warnings	9
Related Documentation	14
Obtaining Documentation	16
Cisco.com	16
Ordering Documentation	16
Documentation Feedback	16
Obtaining Technical Assistance	17
Cisco Technical Support Website	17
Submitting a Service Request	17
Definitions of Service Request Severity	18
Obtaining Additional Publications and Information	18
Overview of Cisco 3700 Series Routers	21
Hardware Features	21
Cisco 3725	21
Cisco 3745	22
Modules, Interface Cards, and Memory	23
Memory	24
Interface Numbering	25
Cisco 3725 Interfaces	25
WAN and LAN Interface Numbering	25
Voice Interface Numbering	26
Cisco 3745 Interfaces	27
WAN and LAN Interface Numbering	27
Voice Interface Numbering	28
Power Supply Options	29
Internal –48 V Telephony Power Modules	29
System Specifications	31
Regulatory Compliance	32
Preparing to Install the Router	33
Safety Recommendations	33
Safety with Electricity	34
Preventing Electrostatic Discharge Damage	34
General Site Requirements	35
Power Supply Considerations	35
Site Environment	36
Site Configuration	36
Equipment Racks	36
Installation Checklist	37
Creating a Site Log	38
Inspecting the Router	38
Required Tools and Equipment for Installation and Maintenance	39
Console and Auxiliary Port Considerations	40
Console Port Connections	40
Auxiliary Port Connections	40
Preparing to Connect to a Network	41
Ethernet Connections	41
Token Ring Connections	42
Serial Connections	42
Configuring Serial Connections	42
Serial DTE or DCE Devices	42
Signaling Standards Supported	43
Distance Limitations	43
Asynchronous/Synchronous Serial Module Data Rates	44
ISDN BRI Connections	44
56-K/Switched-56-kbps DSU/CSU Connections	45
Installing the Router	47
Installing Modules, Interface Cards, and Power Supplies	47
Setting Up the Chassis	48
Setting the Chassis on a Desktop	48
Rack-Mounting the Chassis	49
Attaching Brackets to the Cisco 3725 Router	50
Attaching Brackets to the Cisco 3745 Router	52
Mounting the Router in a Rack	53
Installing the Chassis Ground Connection	54
Cisco 3725 Router Ground Connection	55
Cisco 3745 Router Ground Connection	56
Power Connections	57
Connecting Routers to AC Power	58
Connecting Routers to a DC-Input Power Supply	58
Wiring the DC-Input Power Supply in Cisco 3725 Routers	58
Wiring the DC-Input Power Supply in Cisco 3745 Routers	63
Connecting Routers to the Cisco Redundant Power System	66
Connecting WAN, LAN, and Voice Cables	66
Ports and Cabling	66
Connection Procedures and Precautions	67
Connecting to a Console Terminal or Modem	68
Connecting to the Console Port	68
Connecting to the Auxiliary Port	70
Identifying a Rollover Cable	71
Powering Up the Router	72
Checklist for Power Up	72
Front Panel Indicators	72
Power-Up Procedure	73
Configuring the Router	75
Initial Configuration Using SDM	75
Initial Configuration Using the Setup Command Facility	75
Initial Configuration Using the CLI (Manual Configuration)	78
Troubleshooting	81
Solving Problems	82
Troubleshooting the Power and Cooling Systems	82
Environmental Reporting Features	83
Troubleshooting Modules, Cables, and Connections	83
Reading Front-Panel LEDs	84
Reading Rear Panel LEDs	86
Error Messages	88
Recovering a Lost Password	92
Using the ROMMonitor	93
Entering ROM Monitor Mode	93
Enter ROM Monitor Mode by Using the reload Command	94
Enter ROM Monitor Mode by Resetting the Configuration Register	94
ROM Monitor Commands	94
ROM Monitor Syntax Conventions	95
ROM Monitor Command Descriptions	95
Boot Commands in the ROM Monitor	95
Informational Commands in the ROM Monitor	97
Other Useful ROM Monitor Commands	98
Debugging Commands in the ROM Monitor	98
Configuration Register	98
Modifying the Configuration Register in Menu Mode	99
Modifying the Configuration Register by Hexadecimal Entry	99
Recovering Cisco IOS Software Images	100
Description and Options of the xmodem Command	100
Console Requirements	100
Procedure for the xmodem Command	101
Configuration Register	103
Configuration Register Settings	103
Changing Configuration Register Settings	104
Configuring the Boot Field	105
Enabling Booting from CompactFlash Memory	107

Match case Limit results 1 per page

C-3

Cisco 3700 Series Routers Hardware Installation Guide

OL-2180-08

Appendix C

Configuration Register

Configuring the Boot Field

Step 5

After a few seconds, you see the user EXEC prompt (

Router>

). Enter the

enable

command and your

password to enter privileged EXEC mode:

Router>

enable

Password:

password

Router#

Step 6

At the privileged EXEC prompt (

Router#

), enter the

configure terminal

command:

Router#

configure terminal

Enter configuration commands, one per line.

Edit with DELETE, CTRL/W, and CTRL/U; end with CTRL/Z

Step 7

Enter the

config-register

value

command, where

value

is a hexadecimal number preceded by

(see

Table C-2

), to set the contents of the configuration register:

Router(config)#

config-register 0x

value

Note

Cisco IOS software does not allow you to change the console speed bits directly with the

config-register

command. To change the console speed, complete this sequence:

Router#

configure terminal

Router(config)#

line console 0

Router(config-line)#

speed 9600

Step 8

Press

Ctrl-Z

to exit configuration mode.

Step 9

Copy the new console speed to NVRAM:

Router#

copy run start

The new settings are saved to NVRAM, but they are not effective until the router restarts; for example,

when you switch the power off and on or when you enter a

reload

command from the console.

Step 10

Enter the

show version

command to display the configuration register value currently in effect and the

value that will be used at the next reload. The value is shown on the last line of the display:

Configuration register is 0x142 (will be 0x142 at next reload)

Step 11

Reboot the router. The new value is effective after the router reboots.

Configuring the Boot Field

The lowest four bits of the configuration register (bits 3, 2, 1, and 0) form the boot field

(See

Table C-2

Explanation of Boot Field Configuration Register Bits (00 to 03)

Boot Field

Meaning

Stays at the ROM monitor on a reload or power cycle.

Boots the first image in CompactFlash memory as a system image.

02-F

Enables default booting from CompactFlash memory.

Enables

boot system

commands that override default booting from CompactFlash

memory.