Recovery password of router

[diencu]

Toi co may cau hoi ve recovery password of router can moi nguoi giai quyet gium nhe
1.You work as a network teachnician at Cert.You have completed the password recovery procedure on a Cisco router.The process is sucessful and the router to normal operation.What is configuration register value at this point of time
A.0x2100
B.0x2101
C.0x2124
D.0x2102
E.0x2142
2.What should the configuration register value be after sucessfully completing the password recover procedure and returning the router to normal opertion?
A.0x2100
B.0x2101
C.0x2102
D.0x2124
E.0x2142
3.What is the purpose of pressing the Ctrl+Break keys during the router password recovery procedure ?
A.The restart the router
B.To by pass the configuration in Flash
C.To view the password before changes are mode
D.To by pass setup configuration mode
E.To access ROM monitor mode
4.What is the purpose of typing o/r0x2142 during a password recover procedure on a 2500 series router?
A.To restart the router
B.To by pass the configuration in NVRAM
C.To view the lost passowrd
D.To save the change to the configuration
E.to enter ROM monitor mode
5.What does a configuration register setting of 0x2105 indicate to the router?
A.the boot IOS Code is located in the NVRAM
B.Chech NVRAM for boot system commands
C.By pass NVRAM configuration
D.Boot the IOS Code located in ROM
E.perfrom a password recovery
F.By pass the code in ROM

[admin]

qui trình crack password cisco router:

Qui trình khôi phục password (password recovery)



I. Đối với Cisco 1600, 1700 and 2600 Series Routers:



1. Establish a HyperTerminal (Private Edition 5.0 or higher) console connection with the router.



2. Tắt router, sau đó bật lại. Nhấn Ctrl-Break trong vòng 60 giây



monitor: command "boot" aborted due to user interrupt

rommon 1 >



3. Dùng lệnh confreg để đổi nội dung thanh ghi sang 2142.



rommon 1 >confreg 0x2142



4. Reboot the router with the reset command.



rommon 2 >reset



5. Sau khi reboot, dùng Ctrl-C để vào user mode:



router>



6.



router>enable

router#copy startup-config running-config



7.



router>enable

router#show startup-config



8. Đặt lại password mới:



router#config term

router(config)#enable secret newpassword

router(config)#enable password newpassword

router(config)#line con 0

router(config-line)#login

router(config-line)#password newpassword

router(config)#line aux 0

router(config-line)#login

router(config-line)#password newpassword

router(config)#line vty 0 4

router(config-line)#login

router(config-line)#password newpassword



9. #copy run start



10. Khôi phục giá trị thanh ghi về 0x2102



router#config term

router(config)#config-register 0x2102

router(config)#exit

router#copy running-config startup-config



11. Kiểm tra nội dung thanh ghi



router#show version

Cisco Internetwork Operating System Software

IOS (tm) C2600 Software (C2600-DO3S-M), Version 12.0(5)T1, RELEASE

SOFTWARE (fc1)

Copyright (c) 1986-1999 by cisco Systems, Inc.

Compiled Tue 17-Aug-99 13:18 by cmong

Image text-base: 0x80008088, data-base: 0x80CB67B0

ROM: System Bootstrap, Version 11.3(2)XA4, RELEASE SOFTWARE (fc1)

1 FastEthernet/IEEE 802.3 interface(s)

2 Low-speed serial(sync/async) network interface(s)

32K bytes of non-volatile configuration memory.

8192K bytes of processor board System flash (Read/Write)

Configuration register is 0x2142 (will be 0x2102 at next reload)





Cisco 2500 Series Routers:



1. Thiết lập HyperTerminal (Private Edition 5.0 or higher) console connection with the router.



2. Tắt routers, sau đó bật lại. Nhấn CTRL-BREAK trong vòng 60 giây.



Abort at 0x10EA884 (PC)

>



3. Đổi nội dung thanh ghi thành 0x2142



>o/r 0x2142 (lower case of the letter O for o/r and zero for 0x2142)



4. Reboot router



>i



5. Nhấn Ctrl-C để vào user mode khi router khởi động lại



router>



6. Vào enable mode



router>enable

router#copy startup-config running-config

7. Thực hiện các lệnh show running-config or show startup-config

router#show startup-config



8. Enter a new privileged password and change other lost passwords as may be necessary.



router#config term

router(config)#enable secret newpassword

router(config)#enable password newpassword

router(config)#line con 0

router(config-line)#login

router(config-line)#password newpassword

router(config)#line aux 0

router(config-line)#login

router(config-line)#password newpassword

router(config)#line vty 0 4

router(config-line)#login

router(config-line)#password newpassword



9. Copying the startup-configuration to running-configuration. Thực hiện lệnh no shutdown trên tất cả các interface được dùng.



10. Chuyển nội dung thanh ghi về giá trị ban đầu. Lưu cấu hình



router#config term

router(config)#config-register 0x2102

router#copy running-config startup-config



11. Kiểm tra thanh ghi có giá trị là 2102 bằng lệnh show version



router#show version

Cisco Internetwork Operating System Software

IOS (tm) 2500 Software (C2500-D-L), Version 12.0(4), RELEASE SOFTWARE

(fc1)

Copyright (c) 1986-1999 by cisco Systems, Inc.

ROM: System Bootstrap, Version 5.2(8a), RELEASE SOFTWARE

BOOTFLASH: 3000 Bootstrap Software (IGS-RXBOOT), Version 10.2(8a), RELEASE

SOFTWARE (fc1)

1 Ethernet/IEEE 802.3 interface(s)

2 Serial network interface(s)

1 ISDN Basic Rate interface(s)

32K bytes of non-volatile configuration memory.

8192K bytes of processor board System flash (Read ONLY)

Configuration register is 0x2142 (will be 0x2102 at next reload)

12. Reboot the router.

router#reload

(http://chuyenviet.com/html/articles/passwordrecovery.html)

[duhd]

Tại sao con Cisco 1751 ấn Ctrl-Break trong vòng 60 sau khi bật nguồn mà không vào được ROMMON?
Còn cách nào khác recovery password của con này ko?

[dangquangminh]

Tổ hợp phím Break sẽ phụ thuộc vào chương trình Terminal mà duhd đang dùng. Xem một bảng thống kê ở đây:

http://www.cisco.com/en/US/products/hw/routers/ps133/products_tech_note09186a0080174a34.shtml

Nếu dùng Ctrl-Break không được, thử tắt router rồi bật lại; đồng thời nhấn phím Space Bar trong vòng 2 giây. Qui trình như dưới đây:

How to Simulate a Break Key Sequence
This is useful if your terminal emulator doesn't support the break key, or if a bug prevents it from sending the correct signal (the hyperterminal under Windows NT used to suffer from this behavior):

Connect to the router with the following terminal settings:

1200 baud rate

No parity

8 data bits

1 stop bit

No flow control

You no longer see any output on your screen. This is normal.

Power cycle (switch off and then on) the router and press the spacebar for 10-15 seconds. This generates a signal similar to the break sequence.

Disconnect your terminal and reconnect with a 9600 baud rate. You should now be in ROM Monitor mode.

If all the preceeding methods have failed to properly send a break, you should retry the procedures using a different terminal or PC platform.

Chúc vui vẻ

[duhd]

Cám ơn Anh Đặng Quang Minh
Tôi dùng Ctrl+F6+Break được rồi

Thanks,

[minhtq312]

thanks!!!!!!!!!!!!!!!