路由器的密码恢复:
原理:启动时绕过startup-config的配置(enable密码保存在startup-config),然后重新配置enable密码。
如果要使路由器在启动时绕过startup-config的配置,只有修改配置寄存器的值。正常情况下配置寄存器的值是0x2102==0010.0001.0000.0010,其中第三段的第2个比特位可以控制路由器的启动顺序。如果该位为0,则启动时候运行startup-config的配置,如果该位为1则忽略startup-config的配置,而进入setup模式。
 
从通信服务器上进入某一路由器(以二楼第一机房6号路由器C2600为例)
routerserver#r6
Trying r6 (10.0.0.1, 2006)... Open
 
关闭路由器电源再打开,然后按下CTRL键,不停地按Break键,直到出现rommon1>为止,使路由器进入ROM  Moniror模式。
System Bootstrap, Version 12.2(7r) [cmong 7r], RELEASE SOFTWARE (fc1)
Copyright (c) 2002 by cisco Systems, Inc.
C2600 platform with 131072 Kbytes of main memory
 
 
monitor: command "boot" aborted due to user interrupt
rommon 1 >
rommon 1 >
rommon 1 > confreg 0x2142      改变寄存器的值,让路由器忽略startup-config的配置,而进入Setup模式
 
 
You must reset or power cycle for new config to take effect
rommon 2 > reset    重新启动路由器
 
System Bootstrap, Version 12.2(7r) [cmong 7r], RELEASE SOFTWARE (fc1)
Copyright (c) 2002 by cisco Systems, Inc.
C2600 platform with 131072 Kbytes of main memory
 
program load complete, entry point: 0x80008000, size: 0xe688c8
Self decompressing the p_w_picpath : #################################################
################################################################################
################################################################################
########################## [OK]
 
Smart Init is enabled
smart init is sizing iomem
  ID            MEMORY_REQ                 TYPE
00036B          0X00103980 C2611XM Dual Fast Ethernet
                0X000F3BB0 public buffer pools
                0X00211000 public particle pools
TOTAL:          0X00408530
 
If any of the above Memory Requirements are
"UNKNOWN", you may be using an unsupported
configuration or there is a software problem and
system operation may be compromised.
Rounded IOMEM up to: 5Mb.
Using 3 percent iomem. [5Mb/128Mb]
 
              Restricted Rights Legend
 
Use, duplication, or disclosure by the Government is
subject to restrictions as set forth in subparagraph
(c) of the Commercial Computer Software - Restricted
Rights clause at FAR sec. 52.227-19 and subparagraph
(c) (1) (ii) of the Rights in Technical Data and Computer
Software clause at DFARS sec. 252.227-7013.
 
           cisco Systems, Inc.
           170 West Tasman Drive
           San Jose, California 95134-1706
 
 
 
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600-IK8O3S-M), Version 12.2(11)T,  RELEASE SOFTWARE (
fc1)
TAC Support: [url]http://www.cisco.com/tac[/url]
Copyright (c) 1986-2002 by cisco Systems, Inc.
Compiled Thu 01-Aug-02 12:47 by ccai
Image text-base: 0x8000809C, data-base: 0x818188F4
 
 
Compliance with U.S. Export Laws and Regulations - Encryption
 
This product performs encryption and is regulated for export
by the U.S. Government.
 
This product is not authorized for use by persons located
outside the United States and Canada that do not have prior
approval from Cisco Systems, Inc. or the U.S. Government.
 
This product may not be exported outside the U.S. and Canada
either by physical or electronic means without PRIOR approval
of Cisco Systems, Inc. or the U.S. Government.
 
Persons outside the U.S. and Canada may not re-export, resell,
or transfer this product by either physical or electronic means
without  prior approval of Cisco Systems, Inc. or the U.S.
Government.
 
cisco 2611XM (MPC860P) processor (revision 0x100) with 125952K/5120K bytes of me
mory.
Processor board ID JAD07020UQK (3078295415)
M860 processor: part number 5, mask 2
Bridging software.
X.25 software, Version 3.0.0.
2 FastEthernet/IEEE 802.3 interface(s)
32K bytes of non-volatile configuration memory.
32768K bytes of processor board System flash (Read/Write)
 
 
         --- System Configuration Dialog ---
 
Would you like to enter the initial configuration dialog? [yes/no]: no  不进入对话模式 退回到EXEC模式
 
 
Press RETURN to get started!
 
 
*Mar  1 00:00:14.046: %LINK-3-UPDOWN: Interface FastEthernet0/0, changed state t
o up
*Mar  1 00:00:14.046: %LINK-3-UPDOWN: Interface FastEthernet0/1, changed state t
o up
*Mar  1 00:00:15.048: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthern
et0/0, changed state to down
*Mar  1 00:00:15.048: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthern
et0/1, changed state to down
*Mar  1 00:00:20.613: %LINK-5-CHANGED: Interface FastEthernet0/0, changed state
to administratively down
*Mar  1 00:00:20.613: %LINK-5-CHANGED: Interface FastEthernet0/1, changed state
to administratively down
*Mar  1 00:00:22.384: %SYS-5-RESTART: System restarted --
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600-IK8O3S-M), Version 12.2(11)T,  RELEASE SOFTWARE (
fc1)
TAC Support: [url]http://www.cisco.com/tac[/url]
Copyright (c) 1986-2002 by cisco Systems, Inc.
Compiled Thu 01-Aug-02 12:47 by ccai
*Mar  1 00:00:22.384: %SNMP-5-COLDSTART: SNMP agent on host Router is undergoing
 a cold start
Router>
Router>enable  进入特权模式
Router#copy startup-config running-config  使路由器以前的配置生效,保证以前的配置不丢失。
Destination filename [running-config]?
 
702 bytes copied in 2.488 secs (282 bytes/sec)
Router#config terminal  进入全局模式
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#no enable password  删除使能密码
Router(config)#no enable secret  删除加密的使能密码
Router(config)#config-register 0x2102  把配置寄存器的值改回来,否则以后每次重新启动路由器都进入       setup模式
Router#copy running-config startup-config 保存当前配置
Destination filename [startup-config]?
Building configuration...
[OK]
Router#reload 重新启动
Proceed with reload? [confirm]
 
*Mar  1 00:06:14.950: %SYS-5-RELOAD: Reload requested by console.
System Bootstrap, Version 12.2(7r) [cmong 7r], RELEASE SOFTWARE (fc1)
Copyright (c) 2002 by cisco Systems, Inc.
C2600 platform with 131072 Kbytes of main memory
 
program load complete, entry point: 0x80008000, size: 0xe688c8
Self decompressing the p_w_picpath : #################################################
################################################################################
################################################################################
########################## [OK]
 
Smart Init is enabled
smart init is sizing iomem
  ID            MEMORY_REQ                 TYPE
00036B          0X00103980 C2611XM Dual Fast Ethernet
                0X000F3BB0 public buffer pools
                0X00211000 public particle pools
TOTAL:          0X00408530
 
If any of the above Memory Requirements are
"UNKNOWN", you may be using an unsupported
configuration or there is a software problem and
system operation may be compromised.
Rounded IOMEM up to: 5Mb.
Using 3 percent iomem. [5Mb/128Mb]
 
              Restricted Rights Legend
 
Use, duplication, or disclosure by the Government is
subject to restrictions as set forth in subparagraph
(c) of the Commercial Computer Software - Restricted
Rights clause at FAR sec. 52.227-19 and subparagraph
(c) (1) (ii) of the Rights in Technical Data and Computer
Software clause at DFARS sec. 252.227-7013.
 
           cisco Systems, Inc.
           170 West Tasman Drive
           San Jose, California 95134-1706
 
 
 
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600-IK8O3S-M), Version 12.2(11)T,  RELEASE SOFTWARE (
fc1)
TAC Support: [url]http://www.cisco.com/tac[/url]
Copyright (c) 1986-2002 by cisco Systems, Inc.
Compiled Thu 01-Aug-02 12:47 by ccai
Image text-base: 0x8000809C, data-base: 0x818188F4
 
 
Compliance with U.S. Export Laws and Regulations - Encryption
 
This product performs encryption and is regulated for export
by the U.S. Government.
 
This product is not authorized for use by persons located
outside the United States and Canada that do not have prior
approval from Cisco Systems, Inc. or the U.S. Government.
 
This product may not be exported outside the U.S. and Canada
either by physical or electronic means without PRIOR approval
of Cisco Systems, Inc. or the U.S. Government.
 
Persons outside the U.S. and Canada may not re-export, resell,
or transfer this product by either physical or electronic means
without  prior approval of Cisco Systems, Inc. or the U.S.
Government.
 
cisco 2611XM (MPC860P) processor (revision 0x100) with 125952K/5120K bytes of me
mory.
Processor board ID JAD07020UQK (3078295415)
M860 processor: part number 5, mask 2
Bridging software.
X.25 software, Version 3.0.0.
2 FastEthernet/IEEE 802.3 interface(s)
32K bytes of non-volatile configuration memory.
32768K bytes of processor board System flash (Read/Write)
 
 
 
Press RETURN to get started!
 
 
*Mar  1 00:00:13.942: %LINK-3-UPDOWN: Interface FastEthernet0/0, changed state t
o up
*Mar  1 00:00:13.942: %LINK-3-UPDOWN: Interface FastEthernet0/1, changed state t
o up
*Mar  1 00:00:15.132: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthern
et0/0, changed state to down
*Mar  1 00:00:15.132: %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthern
et0/1, changed state to down
*Mar  1 00:00:16.610: %SYS-5-CONFIG_I: Configured from memory by console
*Mar  1 00:00:17.924: %LINK-5-CHANGED: Interface FastEthernet0/0, changed state
to administratively down
*Mar  1 00:00:17.928: %LINK-5-CHANGED: Interface FastEthernet0/1, changed state
to administratively down
*Mar  1 00:00:20.424: %SYS-5-RESTART: System restarted --
Cisco Internetwork Operating System Software
IOS (tm) C2600 Software (C2600-IK8O3S-M), Version 12.2(11)T,  RELEASE SOFTWARE (
fc1)
TAC Support: [url]http://www.cisco.com/tac[/url]
Copyright (c) 1986-2002 by cisco Systems, Inc.
Compiled Thu 01-Aug-02 12:47 by ccai
*M
 
User Access ar  1 00:00:20.424: %SNMP-5-COLDSTART: SNMP agent on host Router is
undergoing a cold startVerification