Troubleshooting

There are several ways to troubleshoot problems associated with installation and performance. For instance, the LEDs on the front panel are the quickest way to evaluate the operation of the switch, and the statistics provided by the management console or SNMP management station can provide more details about the cause of connectivity and performance problems. In addition, the power-on self-test (POST) determines if the switch is functioning properly when powered on. If the switch does not operate properly or you are unable to access the management console, you can resolve these problems by using the diagnostic console.

Potential problems are discussed under the following topics in this chapter:

• Understanding POST failures

• Diagnosing problems

• Using the diagnostic console

Understanding POST Failures

This section focuses on when the switch detects one or more nonfatal and/or fatal POST failures while running the 13 POST tests. Information about how the switch runs its POST at power up is provided in the "Verifying Your Installation Using the Power-On Self-Test" section in the "Installation" chapter.

If your switch has a fatal POST failure, the switch is not operational and the management console is not available. Contact Cisco Systems.

When a nonfatal POST failure occurs, the SYSTEM LED is amber. Also, a POST failure message, such as the one in Figure 4-1, is displayed on the Management Console Logon Screen. In this example, the switch indicates that ports 1x to 8x and port Ax (or port A) failed POST test 1 (nonfatal--port loopback test).

Catalyst 1900 Management Console
Copyright (c) Cisco Systems, Inc.  1993-1997
All rights reserved.
Ethernet address:      00-E0-1E-7E-B4-40
PCA Number: 73-2239-01
PCA Serial Number: SAD01200001
Model Number: WS-C1924-EN
System Serial Number: FAA01200001
-------------------------------------------------
*** Power On Self Test (POST) failed ***
*** Failed Test(s): 1
*** Failed Port(s): 1 2 3 4 5 6 7 8 A
1 user(s) now active on Management Console.
Press any key to continue.

Table 4-1 lists the individual POST tests in the order they are executed by the switch. This table also describes the POST failures (nonfatal and fatal) and provides information on what the switch does or what you can do when a fatal or nonfatal POST failure is detected. You should contact your system administrator if the switch detects any fatal or nonfatal POST failures.

Diagnosing Problems

Table 4-2 lists symptoms, possible causes, and corrective actions associated with

• Poor performance.

• No connectivity.

• No access to out-of-band management.

Using the Diagnostic Console

The diagnostic console is a menu-drive interface that you can use to perform the following tasks:

• Recover from corrupted firmware

• Recover from a lost or forgotten password

• Reset the switch to factory defaults

• Reset the characteristics of the console port to the factory defaults

How you access the diagnostic console depends on which task you are performing.

Diagnostic Console Logon Screen

To display the Diagnostic Console Logon Screen, follow these steps:

Step 1 Configure the physical characteristics of the terminal or modem to match those of the console port (9600 baud, 8 data bits, 1 stop bit, no parity, no flow control), connect the console port to the terminal or modem, and then start up your terminal emulation program.

Step 2 Disconnect the power cord from the rear panel.

Step 3 Press the Mode button on the front panel, and hold it in.

Step 4 While holding in the Mode button, reconnect the power cord.

The Diagnostic Console Logon Screen shown in Figure 4-2 appears.

-------------------------------------------------
Cisco Systems Diagnostic Console
Copyright(c) Cisco Systems, Inc. 1997
All rights reserved.
Ethernet Address: 00-E0-1E-7E-B4-40
-------------------------------------------------
Press enter to continue.

Diagnostic Console - Systems Engineering Menu

To display the Diagnostic Console - Systems Engineering Menu (see Figure 4-3), press Return on the Diagnostic Console Logon Screen. Use the Diagnostic Console - Systems Engineering Menu to troubleshoot firmware problems and then bring up the firmware as usual.

Diagnostic Console  - Systems Engineering
Operation firmware version:  6.00 Status: valid
Boot firmware version:  3.02
[C] Continue with standard system start up
[U] Upgrade operation firmware (XMODEM)
[S] System Debug Interface
Enter Selection:

WARNING!!! Operation Firmware is invalid
Upgrade firmware to enable switch operation.

[S] System Debug Interface--Use this option to display the Diagnostic Console - System Debug Interface Menu shown in Figure 4-4.

Diagnostic Console - System Debug Interface Menu

To display the Diagnostic Console - System Debug Interface Menu (see Figure 4-4), select the [S] option from the Diagnostic Console - Systems Engineering Menu. Use this menu to reset the console port or the entire switch to the factory defaults. You can also use this menu to display the factory-installed management console password.

Diagnostic Console  - System Debug Interface
[G] Generic I/O
[M] Memory (CPU) I/O
[F] Return system to factory defaults
[R] Reset main console RS232 interface to 9600,8,1,N
[V] View Management Console password
[P] POST diagnostic console
[X] Exit to Previous Menu
Enter Selection:

[F] Return system to factory defaults--Use this option to return the switch to its factory settings. All static and dynamic addresses are removed, as are the IP address and all other configurations. Enter Y (yes) or N (no) and press Return. The changes take effect the next time the switch is reset.

[R] Reset main console RS232 interface to 9600, 8, 1, N--Use this option if you have lost the management console connection because of an improper modem configuration. The next time the switch is reset, the default RS-232 configuration is used.

[V] View Management Console password--Use this option to display the password set for the management console.

[P] POST diagnostic console--For Cisco personnel only.

Recovering from Corrupted Firmware

If the switch firmware has become corrupted, you can access the switch to upgrade the firmware. To recover from corrupted firmware, follow these steps:

Step 1 From the Diagnostic Console - Systems Engineering Menu (Figure 4-3), select the [U] option.

Step 2 Enter Y (yes) at the prompt to confirm the download:

Do you wish to continue with the download process, [Y]es or [N]o?

It can take up to 1 minute to erase the existing firmware.

You are then prompted to choose a transmission speed. Enter 9 (9600) or
5 (57600) at the prompt:

Do you wish to upgrade at [9]600 (console speed) or [5]7600?

The following prompt appears:

Waiting for image at the configured baud rate

Step 3 Start the XMODEM transfer from the application you are running (make sure you have changed the baud rate on the application to match your selection).

The Diagnostic Console Logon Screen is displayed and the switch returns to 9600 baud when the upgrade is complete.

Press Return to display the Diagnostic Console - Systems Engineering Menu, and then select the [C] option to restart the switch using the upgraded firmware.

Recovering from a Lost or Forgotten Password

If you have forgotten the password set for the management console, you can view the password from the Diagnostic Console - System Debug Interface Menu (see Figure 4-4).

To display the password, select the [S] option on the Diagnostic Console - Systems Engineering Menu, and then select the [V] option on the Diagnostic Console - System Debug Interface Menu to display the management console password.

If you want to change the password, select the [M] option on the Console Settings Menu (see Figure 3-4).

Resetting the Switch to Factory Defaults

There can be times when you need the diagnostic console even though the firmware is valid. This could happen, for example, if the switch configuration prevents the firmware from executing properly and you cannot display the management console.

To reset to the switch to the factory defaults, select the [F] option from the Diagnostic Console - Systems Engineering Menu, and press Return. Then select the [C] option from the Diagnostic Console - Systems Engineering Menu to continue with system start up.

Resetting the Management Console to Factory Defaults

To reset to the management console to the factory defaults, follow these steps:

Step 1 Select the [S] option from the Diagnostic Console - Systems Engineering Menu, and press Return to display the Diagnostic Console - System Debug Interface Menu.

Step 2 Select the [R] option from the Diagnostic Console - System Debug Interface Menu, and press Return.

The following are the console port settings for normal operation: 9600 baud,
8 data bits, 1 stop bit, no parity, no flow control.

Step 3 Select the [C] option from the Diagnostic Console - Systems Engineering Menu to continue with system start up.