Cisco Router Password Reset Howto Guide Solution Cannot Login /Unknown Enable Password 2600, 2800, 2900, 3900

It is common that you may get access to undocumented equipment and need to reset the password.  This applies to many Cisco routers whether 2600, 2900, 3900 etc...

Cisco's Guide says to hit Ctrl + Pause/Break but if it doesn't work on some devices causing people to say "cisco password reset pause break does not work", you can see Cisco's alternative key combinations here: 

Step 1: Power Cycle The Router/Switch to enter rommon mode

For Routers like 2900/3900 follow this guide to remove the CF disk first.

Immediately and within 60 seconds hit Ctrl + Pause/Break repeatedly until you see the "rommon 1" prompt.  If the image boots normally to the console, then you've hit the keys too late or maybe you need to check the alternative key combinations above.

Type "confreg 0x2142" and then "reset".  This will then give you root access without authentication.

 

Step 2 - Wait for the reboot, load config and reset the password

Once the image loads, make sure that you hit "no" to the "Would you like to enter the initial configuration dialog".

Type "en" or "enable" to enter enable mode.

copy start run

Then hit "enter" to accept the default destination filename of "running-config"

Now Reset Your Enable Password:

conf t

enable secret oursecretpassword

 

Remember to save the current config:

wr

or

copy run start

 

If you need to reset the console password:

This is wise to do as presumably you don't have access in any other mode at this point and if you exit enable mode you won't be able to re-enter if there is a password on the console.

Be sure to do a "wr" or copy run start after this to save the changes.

 

Step 3 - Reset config register

in config mode you have to set the register back to 2102, otherwise the router will keep booting without the startup config.

config-register 0x2102

 


Tags:

cisco, router, password, reset, howto, login, enable, undocumented, applies, routers, etc, ctrl, pause, doesn, devices, quot, combinations, cycle, rommon, mode, repeatedly, prompt, console, ve, confreg, authentication, reboot, config, loads, initial, configuration, dialog, en, default, destination, filename, conf, oursecretpassword, wr, presumably, register, booting, startup,

Latest Articles

  • FreePBX 17 How To Add a Trunk
  • Docker Container Onboot Policy - How to make sure a container is always running
  • FreePBX 17 How To Add Phones / Extensions and Register
  • Warning: The driver descriptor says the physical block size is 2048 bytes, but Linux says it is 512 bytes. solution
  • Cisco How To Use a Third Party SIP Phone (eg. Avaya, 3CX)
  • Cisco Unified Communication Manager (CUCM) - How To Add Phones
  • pptp / pptpd not working in DD-WRT iptables / router
  • systemd-journald high memory usage solution
  • How to Install FreePBX 17 in Linux Debian Ubuntu Mint Guide
  • How To Install Cisco's CUCM (Cisco Unified Communication Manager) 12 Guide
  • Linux Ubuntu Redhat How To Extract Images from PDF
  • Linux and Windows Dual Boot Issue NIC Won't work After Booting Windows
  • Cisco CME How To Enable ACD hunt groups
  • How to install gns3 on Linux Ubuntu Mint
  • How to convert audio for Asterisk .wav format
  • Using Cisco CME Router with Asterisk as a dial-peer
  • Cisco CME How To Configure SIP Trunk VOIP
  • Virtualbox host Only Network Error Failed to save host network interface parameter - Cannot change gateway IP of host only network
  • Cisco CME and C7200 Router Testing and Learning Environment on Ubuntu 20+ Setup Tutorial Guide
  • Abusive IP ranges blacklist