这些口令可对特权执行和配置模式的访问权限进行保护。使能口令可以恢复,但使能加密口令经过加密,必须替换为新口令。请使用本文档介绍的过程替换 enable secret 口令。
-
将终端或带终端仿真功能的 PC 连接到路由器的控制台端口。使用以下终端设置:
-
9600 波特率
-
无奇偶校验
-
8 个数据位
-
1 个停止位
-
无流控制
有关如何使用电缆将终端连接到控制台端口或 AUX 端口的信息,请参阅以下文档:
-
如果可以访问路由器,请在提示符下键入show version,并记录配置寄存器值。请参阅口令恢复过程示例部分以查看show version命令的输出。
注:配置寄存器通常设置为0x2102或0x102。如果无法再访问路由器(由于登录或TACACS密码丢失),您可以安全地假设您的配置寄存器设置为0x2102
-
使用电源开关关闭路由器,然后重新打开。
-
在看到消息program load complete, entry point: 0x80008000, size: 0x6fdb4c后,在终端键盘上按几次Break,将路由器置于ROMMON中。
注:入口点和大小的值取决于路由器。
如果中断序列不起作用,请参阅用于其他密钥组合的使用标准中断键序列组合进行口令恢复。
如果无法进入 ROMMON 模式,请执行以下步骤:
-
取下闪存。
-
重新加载路由器。路由器最终处于ROMMON模式。
-
插入闪存。
-
执行标准的口令恢复步骤。
-
在rommon 1>提示符处键入confreg 0x2142,以便从闪存启动。
此步骤将会跳过存储口令的启动配置。
-
在 rommon 2> 提示符处键入 reset。
路由器将会重新启动,但是会忽略保存的配置。
-
在每个设置问题后面键入 no,或者按 Ctrl-C 跳过初始设置程序。
-
在 Router>提示符处键入 enable。
您处于启用模式,并看到Router#提示。
-
键入 configure memory 或 copy startup-config running-config,将非易失性 RAM (NVRAM) 复制到内存中。
警告:不输入copy running-config startup-config或write。这些命令将会擦除您的启动配置。
-
键入 show running-config。
show running-config 命令将会显示路由器的配置。在此配置中,在所有接口下将会出现 shutdown 命令,显示当前关闭的所有接口。此外,口令(启用口令、启用加密、vty、控制台口令)可能是加密格式,也可能是未加密格式。您可重复使用未加密的口令,您必须将加密的口令更改为新口令。
-
键入 configure terminal。
此时将会显示 hostname(config)# 提示符。
-
键入enable secret <password>以更改使能加密口令。例如:
hostname(config)#enable secret cisco
-
在所用的每个接口上发出 no shutdown 命令。
如果发出show ip interface brief命令,则要使用的每个接口都必须显示为up up up。
-
键入config-register <configuration_register_value>。其中configuration_register_value是在步骤2中记录的值或0x2102。例如:
hostname(config)#config-register 0x2102
-
按 Ctrl-z 或 end,离开配置模式。
此时将会显示 hostname# 提示符。
-
键入 write memory 或 copy running-config startup-config,以提交更改。
本部分提供了一个口令恢复过程的示例。此示例是使用 Cisco 2900 系列 ISR 创建的。即使您未使用Cisco 2900系列ISR,此输出也为您提供了产品体验的示例。
Router>enable
Password:
Password:
Password:
% Bad secrets
Router>show version
Cisco IOS Software, C2900 Software (C2900-UNIVERSALK9-M), Version 15.0(1)M1,
RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2009 by Cisco Systems, Inc.
Compiled Wed 02-Dec-09 15:23 by prod_rel_team
ROM: System Bootstrap, Version 15.0(1r)M1, RELEASE SOFTWARE (fc1)
c2921-CCP-1-xfr uptime is 2 weeks, 22 hours, 15 minutes
System returned to ROM by reload at 06:06:52 PCTime Mon Apr 2 1900
System restarted at 06:08:03 PCTime Mon Apr 2 1900
System image file is "flash:c2900-universalk9-mz.SPA.150-1.M1.bin"
Last reload reason: Reload Command
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 CISCO2921/K9 (revision 1.0) with 475136K/49152K bytes of memory.
Processor board ID FHH1230P04Y
1 DSL controller
3 Gigabit Ethernet interfaces
9 terminal lines
1 Virtual Private Network (VPN) Module
1 Cable Modem interface
1 cisco Integrated Service Engine-2(s)
Cisco Foundation 2.2.1 in slot 1
DRAM configuration is 64 bits wide with parity enabled.
255K bytes of non-volatile configuration memory.
248472K bytes of ATA System CompactFlash 0 (Read/Write)
62720K bytes of ATA CompactFlash 1 (Read/Write)
Technology Package License Information for Module:'c2900'
----------------------------------------------------------------
Technology Technology-package Technology-package
Current Type Next reboot
-----------------------------------------------------------------
ipbase ipbasek9 Permanent ipbasek9
security securityk9 Permanent securityk9
uc uck9 Permanent uck9
data datak9 Permanent datak9
Configuration register is 0x2102
Router>
!--- The router was just powercycled, and during bootup a
!--- break sequence was sent to the router after seeing the following message
!--- program load complete, entry point: 0x80008000, size: 0x6fdb4c.
rommon 1 > confreg 0x2142
You must reset or power cycle for new config to take effect
rommon 2 > reset
System Bootstrap, Version 15.0(1r)M1, RELEASE SOFTWARE (fc1)
Copyright (c) 2009 by cisco Systems, Inc.
TAC:Home:SW:IOS:Specials for info
C2900 platform with 524288 Kbytes of main memory
program load complete, entry point: 0x80008000, size: 0x6fdb4c
Self decompressing the image : ###############################
##############################################################
##############################################################
##############################################################
############################### [OK]
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 IOS Software, C2900 Software (C2900-UNIVERSALK9-M), Version 15.0(1)M1,
RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2009 by Cisco Systems, Inc.
Compiled Wed 02-Dec-09 15:23 by prod_rel_team
Cisco CISCO2921/K9 (revision 1.0) with 475136K/49152K bytes of memory.
Processor board ID FHH1230P04Y
1 DSL controller
3 Gigabit Ethernet interfaces
9 terminal lines
1 Virtual Private Network (VPN) Module
1 Cable Modem interface
1 cisco Integrated Service Engine-2(s)
Cisco Foundation 2.2.1 in slot 1
DRAM configuration is 64 bits wide with parity enabled.
255K bytes of non-volatile configuration memory.
248472K bytes of ATA System CompactFlash 0 (Read/Write)
62720K bytes of ATA CompactFlash 1 (Read/Write)
--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [yes/no]: n
Press RETURN to get started!
00:00:19: %LINK-3-UPDOWN: Interface BRI0/0, changed state to up
00:00:19: %LINK-3-UPDOWN: Interface Ethernet0/0, changed state to up
00:00:19: %LINK-3-UPDOWN: Interface Ethernet0/1, changed state to up
00:00:19: %LINK-3-UPDOWN: Interface Serial0/0, changed state to down
00:00:19: %LINK-3-UPDOWN: Interface Serial0/1, changed state to down
00:00:20: %LINEPROTO-5-UPDOWN: Line protocol on Interface BRI0/0,
changed state to down
00:00:20: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/0,
changed state to up
Router>
00:00:20: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/1,
changed state to up
00:00:20: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/0,
changed state to down
00:00:20: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0/1,
changed state to down
00:00:50: %SYS-5-RESTART: System restarted --
Cisco IOS Software, C2900 Software (C2900-UNIVERSALK9-M), Version 15.0(1)M1,
RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2009 by Cisco Systems, Inc.
Compiled Wed 02-Dec-09 15:23 by prod_rel_team
00:00:50: %LINK-5-CHANGED: Interface BRI0/0,
changed state to administratively down
00:00:52: %LINK-5-CHANGED: Interface Ethernet0/0,
changed state to administratively down
00:00:52: %LINK-5-CHANGED: Interface Serial0/0,
changed state to administratively down
00:00:52: %LINK-5-CHANGED: Interface Ethernet0/1,
changed state to administratively down
00:00:52: %LINK-5-CHANGED: Interface Serial0/1,
changed state to administratively down
00:00:53: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/0,
changed state to down
00:00:53: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/1,
changed state to down
Router>
Router>enable
Router#copy startup-config running-config
Destination filename [running-config]?
1324 bytes copied in 2.35 secs (662 bytes/sec)
Router#
00:01:24: %LINEPROTO-5-UPDOWN: Line protocol on Interface BRI0/0:1,
changed state to down
00:01:24: %LINEPROTO-5-UPDOWN: Line protocol on Interface BRI0/0:2,
changed state to down
Router#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#enable secret
Router(config)#^Z
00:01:54: %SYS-5-CONFIG_I: Configured from console by console
Router#show ip interface brief
Interface IP-Address OK? Method Status Protocol
Ethernet0/0 10.200.40.37 YES TFTP administratively down down
Serial0/0 unassigned YES TFTP administratively down down
BRI0/0 192.168.121.157 YES unset administratively down down
BRI0/0:1 unassigned YES unset administratively down down
BRI0/0:2 unassigned YES unset administratively down down
Ethernet0/1 unassigned YES TFTP administratively down down
Serial0/1 unassigned YES TFTP administratively down down
Loopback0 192.168.121.157 YES TFTP up up
Router#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#interface Ethernet0/0
Router(config-if)#no shutdown
Router(config-if)#
00:02:14: %LINK-3-UPDOWN: Interface Ethernet0/0, changed state to up
00:02:15: %LINEPROTO-5-UPDOWN: Line protocol on Interface Ethernet0/0,
changed state to up
Router(config-if)#interface BRI0/0
Router(config-if)#no shutdown
Router(config-if)#
00:02:26: %LINK-3-UPDOWN: Interface BRI0/0:1, changed state to down
00:02:26: %LINK-3-UPDOWN: Interface BRI0/0:2, changed state to down
00:02:26: %LINK-3-UPDOWN: Interface BRI0/0, changed state to up
00:02:115964116991: %ISDN-6-LAYER2UP: Layer 2 for Interface BR0/0,
TEI 68 changed to up
Router(config-if)#^Z
Router#
00:02:35: %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, C2900 Software (C2900-UNIVERSALK9-M), Version 15.0(1)M1,
RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2009 by Cisco Systems, Inc.
Compiled Wed 02-Dec-09 15:23 by prod_rel_team
ROM: System Bootstrap, Version 15.0(1r)M1, RELEASE SOFTWARE (fc1)
c2921-CCP-1-xfr uptime is 2 weeks, 22 hours, 15 minutes
System returned to ROM by reload at 06:06:52 PCTime Mon Apr 2 1900
System restarted at 06:08:03 PCTime Mon Apr 2 1900
System image file is "flash:c2900-universalk9-mz.SPA.150-1.M1.bin"
Last reload reason: Reload Command
Cisco CISCO2921/K9 (revision 1.0) with 475136K/49152K bytes of memory.
Processor board ID FHH1230P04Y
1 DSL controller
3 Gigabit Ethernet interfaces
9 terminal lines
1 Virtual Private Network (VPN) Module
1 Cable Modem interface
1 cisco Integrated Service Engine-2(s)
Cisco Foundation 2.2.1 in slot 1
DRAM configuration is 64 bits wide with parity enabled.
255K bytes of non-volatile configuration memory.
248472K bytes of ATA System CompactFlash 0 (Read/Write)
62720K bytes of ATA CompactFlash 1 (Read/Write)
Configuration register is 0x2102
Router#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#config-register 0x2102
Router(config)#^Z
00:03:20: %SYS-5-CONFIG_I: Configured from console by console
Router#show version
Cisco IOS Software, C2900 Software (C2900-UNIVERSALK9-M), Version 15.0(1)M1,
RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2009 by Cisco Systems, Inc.
Compiled Wed 02-Dec-09 15:23 by prod_rel_team
ROM: System Bootstrap, Version 15.0(1r)M1, RELEASE SOFTWARE (fc1)
c2921-CCP-1-xfr uptime is 2 weeks, 22 hours, 15 minutes
System returned to ROM by reload at 06:06:52 PCTime Mon Apr 2 1900
System restarted at 06:08:03 PCTime Mon Apr 2 1900
System image file is "flash:c2900-universalk9-mz.SPA.150-1.M1.bin"
Last reload reason: Reload Command
Cisco CISCO2921/K9 (revision 1.0) with 475136K/49152K bytes of memory.
Processor board ID FHH1230P04Y
1 DSL controller
3 Gigabit Ethernet interfaces
9 terminal lines
1 Virtual Private Network (VPN) Module
1 Cable Modem interface
1 cisco Integrated Service Engine-2(s)
Cisco Foundation 2.2.1 in slot 1
DRAM configuration is 64 bits wide with parity enabled.
255K bytes of non-volatile configuration memory.
248472K bytes of ATA System CompactFlash 0 (Read/Write)
62720K bytes of ATA CompactFlash 1 (Read/Write)
Configuration register is 0x2142 (will be 0x2102 at next reload)
Router#