Recover Cisco Router password – How to recover a lost password on a Cisco router
One of the most frustrating moments as a network administrator is when you desperately want to log in to your Cisco router and you try all possible passwords without success. Luckily, there is a Cisco password recovery process for IOS routers that you can follow and bypass the password control to access the device. Follow the steps below to recover (or change) a forgotten router password:
The following procedure is applicable to almost any Cisco router, such as ISR 800, ISR 900, ISR 1000, 4000 Series, etc.
Step 1:
Connect to the router using the console cable and open your terminal emulation software (like secureCRT). Use normal terminal settings (9600 baud, no parity, 8 data bits, 1 stop bit, no flow control). You will then get a command prompt.
Step 2:
Now you have to power OFF the router from the power switch. Get your keyboard ready and turn the power switch to ON. Immediately press the CTRL + BREAK keys on your keyboard several times until the router enters ROMMON mode. You will see the rommon 1> prompt on your terminal window.
Step 3:
Now you need to change your router’s configuration register. This register is responsible for controlling a number of boot and hardware parameters on the device. The normal value of this register is 0x2102. We will need to change it to 0x2142. This new value tells the router to ignore the boot configuration (where the password is stored) and boot with the factory default configuration (i.e. no password required).
At the rommon prompt, type the following:
Rommon 1> confreg 0x2142
Rommon 2> reset
The “reset” command will reboot the device.
Step 4:
After the router reboots, it will ignore the startup configuration and will behave the same as the first time you turned on the device. Therefore, it will run the initial setup script. Type “no” to the setup request or press “Ctrl-C” to finish the initial setup process.
Step 5:
You will now receive a prompt Router> Type “enable” to enter privileged mode.
Router > enable
Router#
Step 6:
Now we need to load “Startup-Config” into “Running-Config”.
Router#copy startup-config running-config
Attention: DO NOT copy the running configuration to the startup configuration because now that the running configuration is basically empty (factory default) it will delete all your startup configuration.
Step 7:
Now you’re ready to change your password. Change the activation password as below.
Router#config t
Router(config)# enable secrets newpassword
Step 8:
Another important step now is to change the configuration register back to its normal value 0x2102
Router(config)#config-register 0x2102
Step 9:
Now save the configuration and reboot.
Router(config)#exit
Router#write
Router# reload
Step 10:
Once the router boots up, log in with your new password and enable all interfaces (use “no shutdown”) because during recovery the interfaces will be disabled.
So, what we did in the 10 steps above is we bypassed the initial configuration with the forgotten password, and then we got privileged mode without knowing the password. We then load the original configuration into RAM (so we don’t lose it) and impose a new password and save everything back to NVRAM. And then we go back to the original boot sequence.
At this point we have completed the Router Password Recovery Cisco Routers In other words, you have recovered a Cisco router that lost its password.
Good luck!
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