Two common methods to restore a Cisco Router password

This utility

When a Cisco router forgets or loses the enable password, there are two methods to restore it, depending on the series of products you are using.

Method 1

You can use this method to restore the following vrouters: cisco 2000 Series, 2500 series, 3000 series, Cisco 680 series with 4000x0 a6l a CPU, and 10.0 series routers running Cisco IOS systems later than 7000.

Steps:

1. Connect a terminal or a PC with simulation terminal software installed on the console port of the router.

2. Enter the show version command and write down the register value, usually 0x2102 or 0x102. This value is displayed on the last line. Check whether the Break is set to enable or disable in the register configuration.

The default register value is 0x2102. The value ranges from the third digit to the left. If it is 1, it is disable Break. If it is 0, Break is enabled.

3. Shut down the power supply and restart.

4. Press the Break key on the terminal within 60 seconds after the vro starts. The rommon> prompt is displayed. If this is not the case, the terminal does not send a correct interrupt signal to check whether the Break Key is correct or whether it is set to disable.

5. enter o/r0x42 or o/r0x41 at the prompt. o/r0x42 means to boot from Flash memory, and o/r0x41 means to boot from ROMs (note that the first character is the letter o, it is not a number 0 ). It is best to use 0x42. If Flash memory is not installed or erase, 0x41 is used. If 0x41 is available, only view or erase configuration is allowed. You cannot change the password directly.

6. Enter the initialization command at the rommon> prompt.

7. Enter the system configuration dialog prompt and Press "no" until the prompt is displayed. Press RETURN to get started!

8. Press enter and a prompt appears.

9. Enter the enable command and the Router # prompt is displayed.

10. select one of the following options:

If the password is not encrypted, you can directly use the more nvram: startup-config command to view the password. If the password is encrypted, you can only modify the password. Enter the following command:

Router # configure memory

Router # configure terminal

Router (config) # enable secret 1234 abcd

Router (config) # ctrl-z

Router # write memory

11. Enter configure terminal at the EXEC prompt to enter the configuration mode. Enter the config-register command to restore the register value recorded in step 2.

12. Press Ctrl-Z to exit the configuration.

13. In privileged mode, run the write memory command to save the configuration and restart reboot.

Method 2

This method restores the following vrouters: Cisco 1003, 1600, 3600, 4500, 7200, 7500, and IDT Orion-Based.

Steps:

The first four steps are the same as the previous method.

5. At the rommon> prompt, enter the confreg Command, as shown below:

Do you wish to change configuration [y/n]?

Enter yes and press Enter. Select no until "ignore system config info [y/n]?" appears. Enter yes. Then I continued to answer the question by typing "change boot characteristics [y/n]?". Enter yes. Shown as follows:

Enter to boot:

You can select either 2 or 1 at this prompt. If Flash memory is erased is set to 1, you can only view or erase configuration, but cannot directly change the password. It is best to select 2. The following prompt is displayed:

Do you wish to change configuration [y/n]?

Answer no, and press enter to display "rommon> ".

6. Enter the reload command under the Privileged EXEC command.

The following operations are the same as the first method.