Administração de Redes

Password Recovery Cisco - Procedure 1

Use this procedure to recover lost passwords on the following Cisco routers:

Cisco 2000 series
Cisco 2500 series
Cisco 3000 series
Cisco 4000 series with 680x0 Motorola CPU
Cisco 7000 series running Cisco IOS Release 10.0 or later in ROMs installed on the RP card.
The router can be booting Cisco IOS Release 10.0 software in Flash memory, but it needs the actual ROMs on the processor card too.
IGS Series running Cisco IOS Release 9.1 or later in ROMs

To recover a password using Procedure 1, perform the following steps:

Attach a terminal or PC with terminal emulation software to the console port of the router.

Step2 Enter the show version command and record the setting of the configuration register. It is usually 0x2102 or 0x102.

The configuration register value is on the last line of the display. Note whether the configuration register is set to enable Break or disable Break.

The factory-default configuration register value is 0x2102. Notice that the third digit from the left in this value is 1, which disables Break. If the third digit is not 1, Break is enabled.

Step3 Turn off the router, then turn it on.

Step4 Send a Break to the terminal within 60 seconds of turning on the router. (NOTE: In minicom, use CTRL-a followed by f to send a Break; a "Sending BREAK" indication will appear on the screen.)

The rommon> prompt with no router name appears. If it does not appear, the terminal is not sending the correct Break signal. In that case, check the terminal or terminal emulation setup.

Step5 Enter o/r0x42 at the rommon> prompt to boot from Flash memory or o/r0x41 to boot from the boot ROMs.

Note The first character is the letter o, not the numeral zero. If you have Flash memory and it is intact, 0x42 is the best setting. Use 0x41 only if the Flash memory is erased or not installed. If you use 0x41, you can only view or erase the configuration. You cannot change the password.

Step6 At the rommon> prompt, enter the initialize command to initialize the router.

This causes the router to reboot but ignore its saved configuration and use the image in Flash memory instead. The system configuration display appears.

Note If you normally use the boot network command, or if you have multiple images in Flash memory and you boot a non-default image, the image in Flash might be different.

Step7 Enter no in response to the System Configuration Dialog prompts until the following message appears:

Press RETURN to get started!

Step8 Press Return .

The Router> prompt appears.

Step9 Enter the enable command.

The Router# prompt appears.

Step10 Choose one of the following options:

To view the password, if it is not encrypted, enter the more nvram:startup-config command.
To change the password (if it is encrypted, for example), enter the following commands:

Router # configure memory
Router # configure terminal
Router(config)# enable secret 1234abcd
Router(config)# ctrl-z
Router # write memory

Note The enable secret command provides increased security by storing the enable secret password using a non-reversible cryptographic function; however, you cannot recover a lost password that has been encrypted.

Step11 Enter the configure terminal command at the EXEC prompt to enter configuration mode.

Step12 Enter the config-register command and whatever value you recorded in Step 2.

Step13 Press Ctrl-Z to quit from the configuration editor.

Step14 Enter the reload command at the privileged EXEC prompt and issue the write memory command to save the configuration.