How to Recover/Reset Password on Cisco 3925

The Cisco 3925 router is part of a family of networking equipment produced by Cisco, which has been a network equipment giant for many years. Used 3925 routers are available on the Internet at reasonable prices, so acquiring one is not difficult. However, if the password is unknown or lost, reconfiguration is impossible until the password is reset or recovered. Cisco has built in a procedure for rescuing lost or forgotten passwords or entering new passwords.

Things You'll Need: Serial to RJ-45 cable; Terminal emulation software

Instructions

1. Connect your computer to the router with the blue serial-to-RJ-45 cable that came with the router. The 9-pin D-shell end connects to your computer's serial port, while the RJ-45 end connects to the console jack on the router. The RJ-45 end resembles a slightly larger telephone jack connector.

       

2. Turn on your computer and establish a terminal session to the Cisco 3925. You can use any terminal emulator, and many are freely available on the Internet. Configure the session settings as follows:

9600 baud

8 data bits

No parity

1 stop bit

No flow control

Plug the router's power cable into an electrical outlet, and as the 3925 boots, you should see the Cisco boot messages. If you don't see any output on your computer's terminal session, check your settings on the session and restart it if necessary. Press "Break" within 30 seconds of powering on the router to enter rommon (rom monitor) mode.

       

3. Type "confreg 0x2142" and press "Enter" at the "rommon 1>" prompt. This will cause the router to boot from its internal flash memory without loading the configuration into memory. At the following "rommon 2>" prompt, type "reset" and press "Enter." This will cause the router to reload and ignore the previously saved configuration file.

       

4. Respond "no" and press "Enter" when prompted for responses to enter the initial dialog or basic management setup. Type "enable" and press "Enter" at the following "Router>" prompt. This will put you into enable mode and display the "Router#" prompts. Copy the non-volatile memory into memory with the "copy startup-config running-config" command, followed by the "Enter" key. Type "sho run" at the prompt and press "Enter" to display the current configuration, including the passwords, some of which may be encrypted.

       

5. Type "config t" at the prompt and press "Enter." At the "Router(config)#" prompt, type "enable secret <pswd>" -- where "pswd" is the password -- and press "Enter." At this point, your enable password is reset. Press "Ctrl" + "z" to return to the "Router#" prompt.

       

6. Type "config t" at the "Router#" prompts and presses "Enter." At the "Router(config)#" prompt, type "config-register 0x02102" and press "Enter" to reset the boot register to its normal setting. Press "Ctrl" + "z" to leave configuration mode. Type "copy running-config startup-config" and press "Enter" to save your changes. Reboot the router and you should be able to login with your password.

References

• OSIX: How to Reset the Admin Password on a Cisco Router
• ITToolBox: Cisco Router Password Recovery
• Cisco: Cisco 3900 Series, 2900 Series, and 1900 Series Software Configuration Guide

Steps to Reset a Cisco 3900 Series

Cisco 3900 Series Integrated Services Routers (ISR), designed to power the next phase of branch-office evolution, offers unparalleled total cost of ownership savings and network agility through the intelligent integration of security, wireless, and application services.

As a popular Cisco router item, Cisco 3900series offers an upgradable motherboard which allows owners to update hardware as more powerful options become available without having to purchase a new router. Cisco also appeals to environmentally conscious consumers with their EngeryWise dual power supplies, which lower electricity costs and support essential redundancy requirements. It is occasionally necessary to reset this powerful networking device, restoring it to factory default settings.

To reset a Cisco 3900 router, e.g. Cisco3925, Cisco 3945, some Cisco 3900 users have discussed it like that:

About “3945 router password recovery”

Question:

“Hi There,

I understand that the password has to be changed the first time we login to Cisco 3945 router but i failed to do that and it’s not allowing me to connect using default username/password.

Can someone help me in getting this addressed??”      ---From vnirmal112

Answers from others

“You can but you don't have to change the password the first time you login to the 3900.  Are you trying to connect using the console port or telnet?”

“Logged onto router via console...was about to configure a new router...I got a clear message saying that i cannot login next time if i don’t change password, which i saw after logging off only :-(...”

“I am running 12.4.24. If you have another flash card, you can put a different IOS on it and boot it with that and see if you can get in. The other thing you can do is to try the password recovery and see if you can get in that way. Did you ever assign any passwords to it?”

Also frustrated with this Cisco 3900 resetting? Instructions help you reset Cisco 3900 series in detail

Method One

1. Enter "config-register 0x2102" from the router's command prompt window. This gives you access to global configuration mode.

       

2. Enter "show version." The response should read:

router# configure terminal

router (config) #config-register 0x2102

router (config) #end

router#

Repeat the "show version" command.

The response should now read "will be 0x2102 at next reload."

       

3. Enter the command "write erase." This will erase the current start-up configuration.

       

4. Reload the software by entering the "reload" command. Do not save when prompted.

The system display should read:

router#reload

System configuration has been modified. Save? (yes/no): n

Proceed with reload? (confirm)

Confirm that you want the reload to proceed.

       

5. Wait for the reload. The dialog box will read:---System Configuration Dialog---

Would you like to enter the initial configuration dialog? (yes/no)

The router has been reset.

   

Method Two

1.       Enter the command "config-register 0x2142."

The response should read:

Router (config)#config-register 0x2142

Repeat the "show version command."

The response should now read "will be 0x2142 at next reload."

       

2. Reload the software by entering the "reload" command. Do not save when prompted. The system should read:

router#reload

System configuration has been modified. Save? (Yes/no): n

Proceed with reload? (Confirm)

Confirm that you want the reload to proceed.

       

3. Wait for the reload. The dialog box will read:

---System Configuration Dialog---

Would you like to enter the initial configuration dialog? (Yes/no) Enter "no."

     

4. Change the configuration register setting to 0x2102. Enter "config-register 0x2102." Enter "write memory." This will overwrite the running configuration.

       

5. Enter the "reload" command. The system configuration dialog will appear again. The router is reset.

More Related: Cisco 3900 SeriesIntegrated Services Routers: Interfaces and Modules