Tips for clearing router configuration information and passwords

Have you ever encountered this problem in daily network management and maintenance: You have been forcibly rejected by a vro or vswitch, a former "friend", because you forgot your password, parameter resetting and information statistics are not allowed. The following describes how to clear passwords for several common and important network devices ".

Clearing Cisco router configuration information and passwords

Applicable scope: All Cisco 10.0, 2000, 2500, 3000 and 4000 vrouters of IOS 7000 and later versions.
　　
The cleanup procedure is as follows:
　　
1. Connect to the Console port with the serial line of the vro. The following is done through the Win95 Super Terminal;
　　
2. After the router power-on 60 seconds, press CTRL (if not press the CTRL-BREAK) Key, waiting for the prompt ">;
　　
3. type the "> e/s 2000002" command, and record the return value, which will be used in the subsequent "Router (config) # config-register 0x2102" command. (generally, the return value is 2102)
　　
4. Enter "o/r 0x42" after the ">" symbol ";
　　
5. Type "I" and the vro will be reinitialized. If you have any questions, answer No;
　　
6. Type "Enable" (no password, press Enter );
　　
7. Change the password (whether encrypted or not ):
　　
A. Enter "config mem" or "copy startup-config mem ";
　　
B. Enter "write ";
　　
C. Enter "config term" and "enable secret <password>" and "enable password <password>" to change the password;
　　
8. Remove the user prompt and password:
　　
A. Enter the virtual line configuration mode and enter "line vty 0 4 ";
　　
B. Enter "password <password>" to change the password;
　　
C. Enter "login" (you can remove the user prompt, Which is login local );
　　
9. Press Ctrl-z to finish;
　　
10. Enter "write" to save the changes;
　　
11. Enter the privileged configuration mode and type "config-register 0x2102" (note that this step must be completed );
　　
12. Write to save the configuration information;
　　
13. Exit the configuration mode. Reload and restart the vro.
　　
Note: o/r 0x42 is used to guide the router from Flash. If the router fails, you can use o/r 0x41 to guide the router from the ROM. Other operations are the same as o/r 0x42, however, it is best to use it only when Flash Boot fails, Flash content is deleted, or Flash content is not available. With 0x41, you can only view or delete configuration information, but cannot change the password.
　　
　　
Clearing Cisco Catalyst 3000 configuration information
　　
　　
1. When the switch is powered on and started, press and hold the Sys Req button on the back panel of the switch for 5 seconds, and then release it;
　　
2. Go to the configuration menu and select "Clear Non-Volatile RAM" to Clear all configuration information (including passwords) of the vswitch ).
　　
3. reconfigure parameters and passwords as needed.
　　
Clearing Intel Express Switch passwords
　　
Applicability: Intel Express 10 Switch/10 Switch +/100FX Switch
　　
Method 1:
　　
1. Enter the Maintenance Mode of the vswitch (Maintenance Mode), enter: run defparm to restart the vswitch, and change the original configuration to the original default setting (the original default has no password ).
　　
2. Enter the maintenance mode:
　　
A. Close the vswitch and press the Maint button on the panel to power the vswitch;
　　
B. Press the button to keep the System LED green light flashing for 3 seconds;
　　
C. Release the Maint button.
　　
3. Use the serial port of the switch to enter the switch in the terminal mode compatible with VT100 at 9600/N/8/1;
　　
4. Press Enter until the command line prompt is displayed on the screen.
　　
Method 2: Use Intel vswitch Backdoors
　　
Telnet and log on to the vswitch. If you are prompted to enter the user name, enter a common password "debug" to enter the vswitch.
　　
3COM NetServer remote access server
　　
Password cleanup
　　
View the NetServer Configuration DIP switch, which controls the hardware Configuration information of NetServer. In this example, DIP4 controls "Erase/Reinitialize Flash Configuration ".
　　
The cleanup procedure is as follows:
　　
1. Set DIP4 to the on status. When NETServer is started, the Flash-protected configuration information will be deleted;
　　
2. Shut down the machine, set DIP4 to OFF, power it on, and then reconfigure it.