Table Of Contents

Troubleshooting

Contacting Cisco or Your Reseller

Recovering a Lost Password

Changing the Configuration Register

Resetting the Router

Resetting the Password

Resetting the Configuration Register Value

Problem Solving

OK LED Diagnostics

Troubleshooting WICs and VICs

Troubleshooting the Power System

Troubleshooting ISDN

Fan Behavior

Troubleshooting

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Use the information in this chapter to help isolate problems you might encounter with the router or to rule out the router as the source of the problem.

This chapter contains the following sections:

•Contacting Cisco or Your Reseller

•Recovering a Lost Password

•Problem Solving

Contacting Cisco or Your Reseller

If you cannot locate the source of a problem, contact your local reseller for advice. Before you call, you should have the following information ready:

•Chassis type and serial number

•Maintenance agreement or warranty information

•Cisco IOS release installed on your router

•Date you received the router

•Brief description of the problem

•Brief description of the steps you have taken to isolate the problem

•Output from the show tech-support EXEC command

Recovering a Lost Password

This section describes how to recover a lost enable or enable secret password. The process of recovering a password consists of the following major steps:

•Changing the Configuration Register

•Resetting the Router

•Resetting the Password (for lost enable secret passwords only)

•Resetting the Configuration Register Value

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Note See the "Hot Tips" section on Cisco Connection Online (CCO) for additional information on replacing enable secret passwords.

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Changing the Configuration Register

Follow these steps to change the configuration register:

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Step 1 Connect an ASCII terminal or a PC running a terminal-emulation program to the console port on the rear panel of the router. Refer to the section "Connecting a PC" in the "Installation" chapter.

Step 2 Configure the terminal to operate at 9600 baud, 8 data bits, no parity, and 1 stop bit.

Step 3 Reboot the router by pressing the power switch to the off position, and then to the on ( | ) position.

Step 4 At the user EXEC prompt (Router>), enter the show version command to display the existing configuration register value (shown in bold in this example output):

Router> show version

Cisco Internetwork Operating System Software 

IOS (tm) C1700 Software (C1700-SV3Y7-M), Version 12.1(5)XA, EARLY

DEPLOYMENT 

RELEASE SOFTWARE (fc1)

TAC:Home:SW:IOS:Specials for info

Copyright (c) 1986-2000 by cisco Systems, Inc.

Compiled Mon 02-Oct-00 19:28 by philuu

Image text-base: 0x800080DC, data-base: 0x80B7D7A0

ROM: System Bootstrap, Version 12.1(5r)T1, RELEASE SOFTWARE (fc1)

ROM: C1700 Software (C1700-SV3Y7-M), Version 12.1(5)XA, EARLY 
DEPLOYMENT RELEASE SOFTWARE (fc1)

Victrola_3B uptime is 23 hours, 54 minutes

System returned to ROM by power-on

Running default software

cisco 1751 (MPC860) processor (revision 0x5947) with 49152K/16384K 
bytes of memory.

Processor board ID JAB30343106 (4266066989), with hardware revision 
0000

M860 processor: part number 5, mask 1

Bridging software.

X.25 software, Version 3.0.0.

1 FastEthernet/IEEE 802.3 interface(s)

6 Voice FXS interface(s)

32K bytes of non-volatile configuration memory.

8192K bytes of processor board System flash (Read/Write)

Configuration register is 0x0

Step 5 Record the setting of the configuration register. It is usually 0x0.

Step 6 Record the break setting.

•Break enabled—bit 8 is set to 0.

•Break disabled (default setting)—bit 8 is set to 1.

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Resetting the Router

Follow these steps to reset the router:

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Step 1 Do one of the following:

•If break is enabled, go to Step 2.

•If break is disabled, turn the router off, wait 5 seconds, and turn it on again. Within 60 seconds, press the Break key. The terminal displays the ROM monitor prompt. Go to Step 3.

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Note Some terminal keyboards have a key labeled Break. If your keyboard does not have a Break key, refer to the documentation that came with the terminal for instructions on how to send a break. To send a break in Windows HyperTerminal, enter Ctrl-Break.

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Step 2 Send a break. The terminal displays the following prompt:

rommon 2>

Step 3 Enter confreg 0x142 to reset the configuration register:

rommon 2> confreg 0x142

Step 4 Initialize the router by entering the reset command:

rommon 2> reset

The router resets, and the configuration register is set to 0x142. The router boots the system image in Flash memory and displays the following:

--- System Configuration Dialog --- 

Step 5 Enter no in response to the prompts until the following message is displayed:

Press RETURN to get started! 

Step 6 Press Return. The following prompt appears:

Router>

Step 7 Enter the enable command to enter privileged EXEC mode. Configuration changes can be made only in this mode.

Router> enable

The prompt changes to the privileged EXEC prompt:

Router#

Step 8 Enter the show startup-config command to display an enable password in the configuration file:

Router# show startup-config

Step 9 Enter the copy startup-config running-config command to return to your startup configuration:

Router# copy startup-config running-config 

If you are recovering an enable password, skip the following "Resetting the Password" section, and complete the password recovery process by performing the steps in the next section, "Resetting the Configuration Register Value."

If you are recovering an enable secret password, you will not see the display in the show startup-config command output. Complete the password recovery process by performing the steps in the following "Resetting the Password" section.

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Resetting the Password

Follow these steps to reset the password:

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Step 1 Enter the configure terminal command to enter configuration mode:

Router# configure terminal

Step 2 Enter the enable secret command to reset the enable secret password in the router:

Router(config)# enable secret <gobbledegook>

Step 3 Enter the config-register command and the original configuration register value that you recorded in Step 5 in the "Changing the Configuration Register" section earlier in this chapter.

Step 4 Press Ctrl-Z to exit configuration mode.

Router(config)# Ctrl-Z 

Step 5 Save your configuration changes:

Router# copy running-config startup-config

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Resetting the Configuration Register Value

Follow these steps once you have recovered or reconfigured a password:

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Step 1 Enter the configure terminal command to enter configuration mode:

Router# configure terminal

Step 2 Enter the config-register command and the original configuration register value that you recorded in Step 5.

Step 3 Press Ctrl-Z to exit configuration mode:

Router(config)# Ctrl-Z

Step 4 Reboot the router, and enter the recovered password.

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Problem Solving

The key to problem solving is to isolate the problem to a specific subsystem by comparing what the router is doing to what it should be doing.

When problem solving, consider the following subsystems of the router:

•WICs and VICs—Refer to the LEDs on the cards and the LEDs on the router front panel to help identify a failure. For more information on WICs and VICs, refer to the Cisco WAN Interface Cards Hardware Installation Guide that comes with each card.

•Cables—Check all the external cables that connect the router to the network.

•Power system—Check the external power source, power cable, router power supply, and circuit breaker. Check for inadequate ventilation or air circulation that might cause overheating.

•ISDN configuration—Consider ISDN-specific hardware and software configurations (ISDN BRI WICs only).

OK LED Diagnostics

Use the front-panel OK LED to help determine any problems with the router. When the router first boots up, it performs a power-on self-test (POST). If the router detects a problem during the POST, the OK LED blinks in a different pattern (described in Table 3-1), depending on the problem. A pattern is a specific number of blinks that is repeated until the router is turned off. If the router experiences any of these problems, contact your Cisco reseller.

Table 3-1 OK LED Blinking Patterns 

Number of Blinks	Meaning
2	The 860P dual-port RAM (DPRAM) failed.
3	The parameter RAM area of the 860P DPRAM failed.
4	The 860P system protection control register has a write failure.
5	The router cannot detect the dynamic RAM (DRAM).
6	The user programmable machine has a write failure.
9	The router DRAM failed.

Troubleshooting WICs and VICs

Use the show diag command to help determine problems with a card.

Router# show diag

Slot 0:

        C1751 1FE VE DV Mainboard Port adapter, 7 ports

        Port adapter is analyzed 

        Port adapter insertion time unknown

        EEPROM contents at hardware discovery:

        Hardware Revision        : 89.71

        PCB Serial Number        : JAB30343106

        Part Number              : 73-5128-02

        Fab Version              : 04

        EEPROM format version 4

        EEPROM contents (hex):

          0x00: 04 FF 40 02 4D 41 59 47 C1 8B 4A 41 42 33 30 33

          0x10: 34 33 31 30 36 82 49 14 08 02 02 04 FF FF FF FF

          0x20: FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF

          0x30: FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF

          0x40: FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF

          0x50: FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF

          0x60: FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF

          0x70: FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF

        Packet Voice DSP Module Slot 0:

        Hardware Revision        : 2.2

        Part Number              : 73-3815-01

        Board Revision           : A0

        Deviation Number         : 0-0

        Fab Version              : 02

        PCB Serial Number        : ICP0339007X

        RMA Test History         : 00

        RMA Number               : 0-0-0-0

        RMA History              : 00

        Processor type           : 02 

        Number of DSP's          : 2

        Type of DSP              : TMS320C549

        EEPROM format version 4

        EEPROM contents (hex):

        0x00:   04 FF 40 01 5B 41 02 02 82 49 0E E7 01 42 41 30 

        0x10:   80 00 00 00 00 02 02 C1 8B 49 43 50 30 33 33 39 

        0x20:   30 30 37 58 03 00 81 00 00 00 00 04 00 09 02 FF 

        Packet Voice DSP Module Slot 1:

        Hardware Revision        : 2.2

        Part Number              : 73-3741-01

        Board Revision           : A0

        Deviation Number         : 0-0

        Fab Version              : 02

        PCB Serial Number        : ICP0326001Y

        RMA Test History         : 00

        RMA Number               : 0-0-0-0

        RMA History              : 00

        Processor type           : 02 

        Number of DSP's          : 1

        Type of DSP              : TMS320C549

        EEPROM format version 4

        EEPROM contents (hex):

        0x00:   04 FF 40 01 5A 41 02 02 82 49 0E 9D 01 42 41 30 

        0x10:   80 00 00 00 00 02 02 C1 8B 49 43 50 30 33 32 36 

        0x20:   30 30 31 59 03 00 81 00 00 00 00 04 00 09 02 FF 

        WIC Slot 0:

        Dual FXS Voice Interface Card WAN daughter card

        Hardware revision 1.1   Board revision B0

        Serial number     0019621219    Part number    800-02493-02

        Test history      0x00          RMA number     00-00-00

        Connector type    WAN Module

        EEPROM format version 1

        EEPROM contents (hex):

        0x20:   01 0E 01 01 01 2B 65 63 50 09 BD 02 00 00 00 00 

        0x30:   58 00 00 00 00 05 15 01 FF FF FF FF FF FF FF FF 

        WIC Slot 1:

        Dual FXS Voice Interface Card WAN daughter card

        Hardware revision 1.1   Board revision B0

        Serial number     0019621176    Part number    800-02493-02

        Test history      0x00          RMA number     00-00-00

        Connector type    WAN Module

        EEPROM format version 1

        EEPROM contents (hex):

        0x20:   01 0E 01 01 01 2B 65 38 50 09 BD 02 00 00 00 00 

        0x30:   58 00 00 00 00 05 15 01 FF FF FF FF FF FF FF FF 

        WIC Slot 2:

        Dual FXS Voice Interface Card WAN daughter card

        Hardware revision 1.1   Board revision B0

        Serial number     0019621204    Part number    800-02493-02

        Test history      0x00          RMA number     00-00-00

        Connector type    WAN Module

        EEPROM format version 1

        EEPROM contents (hex):

        0x20:   01 0E 01 01 01 2B 65 54 50 09 BD 02 00 00 00 00 

        0x30:   58 00 00 00 00 05 15 01 FF FF FF FF FF FF FF FF 

The show diag command displays similar information for each port available on the router.

Table 3-2 lists problems that could occur with the WICs and VICs and the possible solutions of these problems.

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Table 3-2 Troubleshooting WICs and VICs 

Symptom	Possible Solutions
Router does not recognize the card.	•Confirm that the Cisco IOS release installed in the router supports the WIC or VIC. •Make sure you have a Cisco IOS feature set that supports voice. The Cisco WAN Interface Cards Hardware Installation Guide lists the software requirements for each card. •Make sure that the card is correctly installed in the router. Refer to the "Installing WICs and VICs" section in the "Installation" chapter.
Router recognizes the cards, but the card ports do not initialize.	•Make sure that the card is correctly installed in the router. Refer to the "Installing WICs and VICs" section in the "Installation" chapter. •Check the external cable connections to make sure they are secure.
Router does not boot properly or continuously or intermittently reboots.	Make sure that the WIC or VIC is correctly installed in the router. Refer to the "Installing WICs and VICs" section in the "Installation" chapter.
Router does not boot or reset after the WIC or VIC is inserted.	There might be a short. Turn off the router immediately.
Router boots, but the console screen is frozen.	•Make sure the console cable is securely connected to the router and to the PC or terminal. •Verify that the parameters for your terminal are set to the following: –9600 baud –8 data bits –No parity –1 stop bit –no flow control
Router powers on and boots only when a particular WIC or VIC is removed from the router.	•Confirm that the Cisco IOS release installed in the router supports the WIC or VIC. The Cisco WAN Interface Cards Hardware Installation Guide lists the software requirements for each card. •The router might be overheating. Contact your Cisco reseller.
Router powers on and boots only when a particular cable is disconnected.	There might be a problem with the WIC or VIC cables. Consult your Cisco reseller for warranty information.

Troubleshooting the Power System

If the router external power supply fails, return it to your Cisco reseller. Table 3-3 lists symptoms and possible solutions of power problems.

Table 3-3 Troubleshooting the Power System

Symptom	Possible Solution(s)
Router shuts down after being on for a short time.	•Make sure that the area in which the router is installed meets the environmental site requirements in the "Technical Specifications" appendix in this guide and in the "Site Requirements" section in the Regulatory Compliance and Safety Information for Cisco 1700 Routers document that came with your router. •Make sure nothing is blocking the fan vent on top of the router. •If the front-panel PWR LED is not on, the power supply has failed.
The router attempts to boot, but all LEDs remain off.	The power supply has failed. Return the router to your Cisco reseller.
The router is on, but the front-panel PWR LED is off.	The power supply has failed. Return the router to your Cisco reseller.
The front-panel PWR LED is on, the front-panel OK LED is off, and the router does not pass console or EIA data.	The power supply has failed. Return the router to your Cisco reseller.

Troubleshooting ISDN

Because ISDN uses many variables and supports many different configurations, it sometimes can cause problems for the router. This section describes problems related to the ISDN line that might occur.

Two commands are useful when troubleshooting ISDN:

•For routers with an ISDN S/T WIC, enter the clear interface command to terminate any active ISDN calls and to reset the ISDN BRI interface. Do this for each ISDN port installed in the router:

Router# clear interface bri0/0

Router# clear interface bri1/0

•For routers with an ISDN U WIC, use the clear controller command to terminate any active ISDN calls, to reset the ISDN BRI interface, and to reset the ISDN line between the router and the central office switch. Do this for each ISDN port installed in the router:

Router# clear controller bri0

Router# clear controller bri1

Table 3-4 lists troubleshooting methods for ISDN-specific problems that might occur.

Table 3-4 Troubleshooting ISDN 

WIC	Symptom	Check the Following	Possible Solution(s)
ISDN S/T	Router is on, but the OK LED on the card is off.	Is the OK LED on the router front panel on?	If no, the router might be malfunctioning. Contact your Cisco reseller.
		Are all ISDN cables properly connected?	If yes, the ISDN line might be malfunctioning. Check with your ISDN service provider.
		Is the NT1 LED on?	If no, the NT1 might be malfunctioning.
ISDN U	Router is on, but the NT1 LED on the card is off.	Is the OK LED on?	If no, the router might be malfunctioning. Contact your Cisco reseller.
		Are all ISDN cables properly connected?	If yes, the ISDN line might be malfunctioning. Check with your ISDN service provider.
		Is the ISDN line connected to the card ISDN U port?	If yes, the ISDN line might be malfunctioning. Check with your ISDN service provider.
ISDN S/T or ISDN U	Card cannot make a connection to the remote router.	Use show isdn status command to check the following:
		Does the current ISDN switch type match actual switch type being used?	Use the isdn switch-type command to configure correct switch type.
		Is Layer 1 status deactivated?	Use the show controller bri0 command to check for the messages CO RUNNING LOOPBACK TESTS or CO TESTING. If you receive these messages, contact the service provider.
		If Layer 1 status is active, does Layer 3 status say "2 Active Layer 3 calls"?	Router might have called itself. Check destination phone number configured with the dialer map command or the dialer string command.
		If Layer 1 status is active, does Layer 3 status say "No Active Layer 3 call(s)"?	Check destination phone number and make sure it matches the remote router phone number. Check route to the destination and make sure it matches the remote router network address.
		If Layer 1 status is active, does Layer 3 status say "1 Active Layer 3 call"?	Check router protocol configurations.

Fan Behavior

Under normal operation, the fan on the Cisco 1751 router is off. The fan turns on automatically, as required, to cool the system.