Tài liệu QUY TRÌNH KHÔI PHỤC PASSWORD (password recovery) pptx

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QUY 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



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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)



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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



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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)



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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