15º Post - Nova senha através do config-register

Para inserir uma nova senha no router:

Quando estiver inicializando, pressiona Ctrl+break, ele irá carregar o ROM MON, um sistema operacional menor usado normalmente para troca de senha;
Digite confreg 0x2142, irá alterar o valor do registrador para não carregar o arquivo de configuração startup config;
Digite reset, o router será reinicializado;
O router irá perguntar se você quer ir para o modo SETUP, digite NO;
Acesse o modo privilegiado, digitando ENABLE;
Copie o conteúdo da NVRAM para RAM com o comando copy startup-config running-config;
Acesse o modo de configuração global com o comando configure terminal;
Insira uma nova senha com o comando enable secret "nova senha";
Altere o valor do registrador de configuração com o comando config-register 0x2102;
Volta para o modo privilegiado, e salve as alterações com o comando copy running-config startup-config.

Segue abaixo um exemplo no packet tracer:

System Bootstrap, Version 12.3(8r)T8, RELEASE SOFTWARE (fc1)

Cisco 1841 (revision 5.0) with 114688K/16384K bytes of memory.

Self decompressing the image :

###########System Bootstrap, Version 12.3(8r)T8, RELEASE SOFTWARE (fc1)

Cisco 1841 (revision 5.0) with 114688K/16384K bytes of memory.

Self decompressing the image :

###############

monitor: command "boot" aborted due to user interrupt

rommon 1 > confreg 0x2142

rommon 2 >

rommon 2 > reset

System Bootstrap, Version 12.3(8r)T8, RELEASE SOFTWARE (fc1)

Cisco 1841 (revision 5.0) with 114688K/16384K bytes of memory.

Self decompressing the image :

########################################################################## [OK]

Restricted Rights Legend

Use, duplication, or disclosure by the Government is

subject to restrictions as set forth in subparagraph

Rights clause at FAR sec. 52.227-19 and subparagraph

Software clause at DFARS sec. 252.227-7013.

cisco Systems, Inc.

170 West Tasman Drive

San Jose, California 95134-1706

Cisco IOS Software, 1841 Software (C1841-ADVIPSERVICESK9-M), Version 12.4(15)T1, RELEASE SOFTWARE (fc2)

Technical Support: http://www.cisco.com/techsupport

Compiled Wed 18-Jul-07 04:52 by pt_team

Image text-base: 0x60080608, data-base: 0x6270CD50

This product contains cryptographic features and is subject to United

States and local country laws governing import, export, transfer and

use. Delivery of Cisco cryptographic products does not imply

third-party authority to import, export, distribute or use encryption.

Importers, exporters, distributors and users are responsible for

compliance with U.S. and local country laws. By using this product you

agree to comply with applicable laws and regulations. If you are unable

to comply with U.S. and local laws, return this product immediately.

A summary of U.S. laws governing Cisco cryptographic products may be found at:

http://www.cisco.com/wwl/export/crypto/tool/stqrg.html

If you require further assistance please contact us by sending email to

export@cisco.com.

Cisco 1841 (revision 5.0) with 114688K/16384K bytes of memory.

Processor board ID FTX0947Z18E

M860 processor: part number 0, mask 49

2 FastEthernet/IEEE 802.3 interface(s)

191K bytes of NVRAM.

63488K bytes of ATA CompactFlash (Read/Write)

Cisco IOS Software, 1841 Software (C1841-ADVIPSERVICESK9-M), Version 12.4(15)T1, RELEASE SOFTWARE (fc2)

Technical Support: http://www.cisco.com/techsupport

Compiled Wed 18-Jul-07 04:52 by pt_team

--- System Configuration Dialog ---

Continue with configuration dialog? [yes/no]:

Continue with configuration dialog? [yes/no]: no

Press RETURN to get started!

Router>enable

Router#copy startup-config running-config

Router#configure terminal

Enter configuration commands, one per line. End with CNTL/Z.

Router(config)#enable secret router1

Router(config)#config-register 0x2102

Router(config)#exit

Router#

%SYS-5-CONFIG_I: Configured from console by console

Router#copy running-config startup-config

Destination filename [startup-config]?

Building configuration...

[OK]

Router#show version

Cisco IOS Software, 1841 Software (C1841-ADVIPSERVICESK9-M), Version 12.4(15)T1, RELEASE SOFTWARE (fc2)

Technical Support: http://www.cisco.com/techsupport

Compiled Wed 18-Jul-07 04:52 by pt_team

ROM: System Bootstrap, Version 12.3(8r)T8, RELEASE SOFTWARE (fc1)

System returned to ROM by power-on

System image file is "flash:c1841-advipservicesk9-mz.124-15.T1.bin"