Wednesday, April 27, 2011

Cisco Switches password recovery

Console cable connect to pc and open hyperterminal or SecureCRT

power up switch

press mode butten 1 mins

check the file at flash:
dir flash:
change config.txt ... something like that ... config.old

Procedure with Password Recovery Enabled

If the password-recovery mechanism is enabled, this message appears:

The system has been interrupted prior to initializing the flash file system. The following
commands will initialize the flash file system, and finish loading the operating system




Step 1 Initialize the flash file system:

switch: flash_init

Step 2 If you had set the console port speed to anything other than 9600, it has been reset to that particular speed. Change the emulation software line speed to match that of the switch console port.

Step 3 Load any helper files:

switch: load_helper

Step 4 Display the contents of flash memory:

switch: dir flash:

The switch file system appears:

Directory of flash:

13 drwx 192 Mar 01 1993 22:30:48 c3750-ipservices-mz-122-25.SEB

11 -rwx 5825 Mar 01 1993 22:31:59 config.text

18 -rwx 720 Mar 01 1993 02:21:30 vlan.dat

16128000 bytes total (10003456 bytes free)

Step 5 Rename the configuration file to config.text.old.

This file contains the password definition.

switch: rename flash:config.text flash:config.text.old

Step 6 Boot the system:

switch: boot

You are prompted to start the setup program. Enter N at the prompt:

Continue with the configuration dialog? [yes/no]: N

Step 7 At the switch prompt, enter privileged EXEC mode:

Switch> enable

Step 8 Rename the configuration file to its original name:

Switch# rename flash:config.text.old flash:config.text

Note Before continuing to Step 9, power on any connected stack members and wait until they have completely initialized. Failure to follow this step can result in a lost configuration depending on how your switch is set up.

Step 9 Copy the configuration file into memory:

Switch# copy flash:config.text system:running-config
Source filename [config.text]?
Destination filename [running-config]?

Press Return in response to the confirmation prompts.

The configuration file is now reloaded, and you can change the password.

Step 10 Enter global configuration mode:

Switch# configure terminal

Step 11 Change the password:

Switch (config)# enable secret password

The secret password can be from 1 to 25 alphanumeric characters, can start with a number, is case sensitive, and allows spaces but ignores leading spaces.

Step 12 Return to privileged EXEC mode:

Switch (config)# exit

Step 13 Write the running configuration to the startup configuration file:

Switch# copy running-config startup-config

The new password is now in the startup configuration.

Note This procedure is likely to leave your switch virtual interface in a shutdown state. You can see which interface is in this state by entering the show running-config privileged EXEC command. To re-enable the interface, enter the interface vlan vlan-id global configuration command, and specify the VLAN ID of the shutdown interface. With the switch in interface configuration mode, enter the no shutdown command.

Step 14 Reload the switch stack:

Switch# reload


confreg 2142

after finished recovery put it back normal confreg

config 2102

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