unable to recover the password using confreg=0x2142 on Cisco 4506

[Saji Thomas]

Hello,

I tried the steps mentioned in the links below:

http://www.cisco.com/en/US/products/hw/switches/ps663/products_password_recovery09186a00800945f7.shtml
http://www-tss.cisco.com/eservice/compass/common/activities/password_1700.htm
http://www-tss.cisco.com/eservice/compass/common/activities/password_cat_6000CatOS.htm the other similar resolutions on the cisco/other website but none of them works for the Cisco 4506 switch I have.

1. Reboot

2. Press the "CTRL + C" button on the laptop to put the router into ROMMON mode.
Result: Works fine and gets into the ROMMON 1 mode.

3. confreg 0x2142
Result: This one does not work. confreg=0x2142 and that command is accepted by the switch but it does not tell us that we have to restart to make the changes. Now it goes ROMMON 2 mode.

4. reset
Result: I type reset and the switches seems to be power cycled but it again goes to the password prompt which I dont know and this is the password that I am trying to recover or break.

I never get the option to follow the steps after this point.

Any help would be appreciated.

Thanks!!!!

[Ramon Thomas]

I was able to resolve this problem by entering confreg then working through the prompts with one major change, instead of reset at the end of the sequence as the doc specifies I entered the  "boot" command :

rommon 2 >confreg

Configuration Summary :

=> load rom after netboot fails

=> console baud: 9600

=> autoboot from: commands specified in 'BOOT' environment variable

do you wish to change the configuration? y/n  [n]:  y

enable  "diagnostic mode"? y/n  [n]:  n

enable  "use net in IP bcast address"? y/n  [n]:

disable "load rom after netboot fails"? y/n  [n]:

enable  "use all zero broadcast"? y/n  [n]:

enable  "break/abort has effect"? y/n  [n]:

enable  "ignore system config info"? y/n  [n]:  y

change console baud rate? y/n  [n]:

change the boot characteristics? y/n  [n]:

Configuration Summary :

=> load rom after netboot fails

=> ignore system config info

=> console baud: 9600

=> autoboot from: commands specified in 'BOOT' environment variable

do you wish to save this configuration? y/n  [n]:  y

You must reset or power cycle for new configuration to take effect

rommon 3 >boot

[Telsource NMC]

i just ran into this very same issue with a Cat 4500X.  the command confreg 0x2142 would out put with "usage: confreg" while in rommon.  it would never actually change the reg set up.  i ended up having to find another cisco page that showed what each reg code actually means  (and ill provide a link to the site i went to) in order to get it to change to, what i ended up needing to use 0x2141.  in the section below i ended up having to make a few changes to make it happen.  and ill show the changes i made to make it the 2142 or 2141

rommon 2 >confreg

Configuration Summary :
=> ignore system config info
=> console baud: 9600
=> autoboot from: commands specified in 'BOOT' environment variable

do you wish to change the configuration? y/n [n]: y
enable "diagnostic mode"? y/n [n]:
enable "use net in IP bcast address"? y/n [n]:
enable "load rom after netboot fails"? y/n [n]:Y
enable "use all zero broadcast"? y/n [n]:
enable "break/abort has effect"? y/n [n]:Y
disable "ignore system config info"? y/n [n]:Y

change console baud rate? y/n [n]:

change the boot characteristics? y/n [n]: y

enter to boot:
0 = disable autoboot
1 = the first file from internal flash device
2 = commands specified in 'BOOT' environment variable
[2]:(when i changed this to (2) the reg at reset was 0x2 not sure why but should have actually been 0x2142, but changing it to 1 did make the reg 0x2141 with the above bold changes.

this is the config summary I ended up having to use to make it work

Configuration Summary :
=> load rom after netboot fails
=> ignore system config info
=> console baud: 9600
=> autoboot from: the first file from internal flash device

here is the cisco link that helped me figure out what parts i needed to activate and deactivate to make the reg i did.

https://www.cisco.com/c/en/us/support/docs/routers/10000-series-routers/50421-config-register-use.html

i hope this helps other that encounter my issue in the future.

Joseph Blosser