Solve the Problem of forgetting the Cisco Router password

Cisco routers are widely used in network interconnection. Among them, 2500 series routers are widely used in low-end users. So what if you accidentally forget the superuser password of the 2500 series router? Don't be afraid, as long as you can restore as follows:
Preparation: a computer running Terminal simulation program can start a Super Terminal in Windows 95/98), and the microcomputer serial port COM1/COM2) is connected to the Console port of the router through the configuration line randomly assigned by Cisco.
Recovery steps:

1. When a vro is started, press the Break Key within 60 seconds according to the technical manual provided by Cisco.

2. enter the "> e/s 2000002" command, and record the return value before "> o/r 0x142) # Replace 2102 In the config-register 0x2102 "command. The common return value is 2102, But what if not ?).
3. initialize the vro: "> I ".

4. When the system restarts, the screen displays the system configuration dialog: "policystem restart aiton to get started ?, Type "no". The system displays "Press RETURN to get started! ", Press the" Return "key, and the system displays" Router> ".

5. run the following command: "Router> enable" to enter the Super User status (the system no longer requires you to enter the super password); "Router # show startup-config" to display the configuration parameters, note that you can use the enable serect "changepassword" command to change the superuser password ).

6. There are two ways to continue working.

A. Restart the vro directly, continue with step 1, and type "> o/r 0x2102", that is, the returned value recorded), and enter "> I.
B. type the following command:
"Router # copy start run" first copies the configuration file to the memory)
"Router # config t"
"Router (config) # config-register 0x2102" indicates the returned value)
"Router (config) # Ctrl + z"
"Router # write change config-register and save the configuration file ")
"Router # reload"
This method applies not only to Cisco2500, but also to Cisco2000, Cisco3000, Cisco4000, and Cisco7000.

7. Restart the vrouter to "Router # reload ".