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!!!!

[Reza Sharifi]

Hi,

What happen if you just type "confreg" without 0x2142?

does it ask all those questions?

Reza

[Saji Thomas]

Hello Reza,

No confreg alone also does not work. Only command that works at ROMMON1>confreg=0x2142

Also other options, i.e. confreg, confreg 0x2142 gives command not found error.

If I use confreg command, it says user redirection is not available at this time or an error something like that.

Thanks for the reply!!!

[Reza Sharifi]

Hi Saji,

When in Rommon, can you try posting the output of "help" command to see what commands are available?

after you change the confreg, do you the option to type "i" for initialization?

Reza

[Saji Thomas]

By the way, I am going to try to rename the start up file and see if that does the trick on not.

Will keep my fingers crossed and will update the thread.

Thanks to everyone who read the thread and tried to help.

Regards!!!!!!

[ohassairi]

there's no save command after changing the register ?

[Leo Laohoo]

Try "confreg 2142".

[Peter Paluch]

Leo,

CAUTION - USING 2142 INSTEAD OF 0x2142 WILL MAKE TROUBLE! All recommended values of configuration register are indicated in hexadecimal, and all the commands modifying the configuration register interpret the indicated value either as decimal if no '0x' prefix is indicated. Thus using "confreg 2142" is equivalent to "confreg 0x85e" which is certainly something you do not want. Very often, these kinds of mistakes result, among others, to the modification of bits that identify the console port speed, resulting usually in immediate loss of console connectivity until the new console speed is guessed by trial-and-error.

Best regards,

Peter

[Saji Thomas]

Reply to all of your comments:

1) ohassairi: I am not aware of any save command. May be any expert can help.
2) leolaohoo: confreg 2142 may cause issues as per Peter Paluch below.
3) Peter Paluch: Thanks for the word of caution.I will try all this option tommorow and let you guys know.

Also, FYI....its a old switch that was not used but now we plan to use it with a 6509. 6509 will use the cat6e cables and the 4506 will use the existing cat5e cables. I am also planning to have a ethernet channel between the two but thats a later thing to be done. As of now, just want to reset the 4506 switch. THATS ALL!!!!

Thanks again...all of you. I will update you guys soon.

[Peter Paluch]

Saji,

One more comment: you have indicated repeatedly that you have entered a command in the form of confreg=0x2142. The equal sign, however, is incorrect here and is also not indicated in the document about password recovery for SUP on 4500 series. The correct syntax uses a whitespace, i.e.: confreg 0x2142 - can you try that?

Best regards,

Peter

[Saji Thomas]

Hello Peter,

I mentioned in the initial post in point 3. I tried confreg 0x2142 and that says command not found. Is it someway related to the version of the engine or the version of the CATOS or IOS. I am very sure that it has Cisco IOS because CAT OS will not take confreg 0x2142 command.

Only command that works on the switch I have is confreg=0x2142. No other version of confreg works.

[Saji Thomas]

***********UPDATE**********

I used the confreg=0x2142 in rommon1.

Used reset in rommon 2

Restarted the switch and it brings the switch to the EXEC mode. Earlier it was asking a password to enter in EXEC mode also.

Now when I enter en at >prompt to enter priviledge mode, it again asks for the password.

I want to remove all the passwords and it should work as mentioned in the cisco docs where you get the option to configure everything again.

Any help would be appreciated.

########UPDATE########

[ccrank]

I had the same issue and it was the = sign that was creating the error.

[Leo Laohoo]

Hi Peter,

Didn't know this.  When I was toying with the confreg values (I think I was using 2600) "confreg 2142" or "confreg 2102" was acceptable.

Besides, you'll know if the the value entered is incorrect when you do a "sh ver" or "sh hardware" and you'll see the value.

[chris.256]

Hi Seji, If you still have the probelm, Try in ROMMON typing "confreg" and follow the prompt see my example. It worked for me :-)

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 >reset