| 作为一个网络管理员或是工程师，
不仅仅是知道怎么去操作cisco路由器或其他cisco设备；
还应该有未雨绸缪的意识，
当设备遭到非物理破坏（非硬件破坏，只是操作系统被破坏）时，
能够快速地让它们恢复正常工作；
或是对于新买的设备（没有操作系统），怎么才能让它们运作起来？
其实，对于硬件来说，一般不易遭到破坏，
一旦被破坏了，想恢复也难了。
所谓未雨绸缪，也即是在系统正常运作的时候，
将系统备份到服务器上，以便需要时，可以直接从服务器上还原；
1）将cisco路由器的IOS备份到tftp服务器并且还原；
a、搭建TFTP服务器；
其实，非常简单，只需要下载一个TFTP工具软件，
而后安装，完成后将tftp应用程序打开；
对于安装tftp软件的PC也就是一台TFTP服务器；
b、在tftp服务器上进行简单设置；
如图：（59）
在tftp控制台上，
选择中间按钮（符似蝴蝶）打开，
自定义一下TFTP log以及tftp root的文件路径，方便管理；
c、联通TFTP服务器与路由器
（对于PC作为服务器，使用交叉线连接）；
TFTP服务器ip192.168.1.6，
路由器连接到服务器使用的ethernet口ip192.168.1.66，
ping一下，检查一下是否联通；
d、进行系统的备份；
(说明：在备份和还原时，必须明确哪是服务器，哪是客户端；
因为执行操作一直是在客户端；）
进入路由器执行操作（客户端）：
louzuoen(config)#int ethernet 0
louzuoen(config-if)#ip add 192.168.1.66 255.255.255.0
(配置路由器连接到服务器使用的ethernet口ip）
louzuoen(config-if)#no sh
louzuoen(config-if)#end
louzuoen#sh run
（查看配置的IP）
Building configuration... Current configuration : 890 bytes
!
version 12.1
no service single-slot-reload-enable
service timestamps debug uptime
service timestamps log uptime
service password-encryption
service udp-small-servers
service tcp-small-servers
!
hostname louzuoen
!
enable secret 5 $1$Yt6O$vZjJOceMfnm23jXbeM8A8/
enable password 7 124C5147
!
ip subnet-zero
no ip domain-lookup
!
interface Ethernet0
ip address 192.168.1.66 255.255.255.0
no ip route-cache
no ip mroute-cache
line con 0
exec-timeout 0 0
password 7 005D4753560B
logging synchronous
login
line aux 0
transport input all
line vty 0 4
password 7 144E465E5E54
login
!
end louzuoen#ping 192.168.1.6
（测试一下联通性）
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.6, timeout is 2 seconds:
.!!!!
Success rate is 80 percent (4/5), round-trip min/avg/max = 1/2/4 ms louzuoen#sh flash
（查看一下flash即查看其中的目录）
System flash directory:
File Length Name/status
1 8039948 louzuoen
（注意一下：此flash中只有一个目录；若有多个目录（存放IOS文件），
在备份时必须指定相应的目录，如copy flash：目录名 tftp）
[8040012 bytes used, 8737204 available, 16777216 total]
16384K bytes of processor board System flash (Read ONLY)
（此时flash只读，因为系统从flash启动，系统正在使用flash中的IOS) louzuoen#copy fla tftp
（copy时，注意copy+源+目的）
Source filename []? louzuoen
Address or name of remote host []? 192.168.1.6
（远程主机的IP，也即tftp服务器的IP）
Destination filename [louzuoen]?
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
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!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
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!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
（在备份时必须注意，若其中出现了原点‘.’，
则表示文件有丢失，必须执行组合键ctrl+shift+6强行中止，重新备份）
8039948 bytes copied in 183.660 secs (43934 bytes/sec)
（全部为‘!’，备份成功）
louzuoen# e、进行系统的还原；
（1）模拟环境；
louzuoen#conf t
Enter configuration commands, one per line. End with CNTL/Z.
louzuoen(config)#co
louzuoen(config)#config-register 0x2101
（修改寄存值，让路由器从ROM中迷你的IOS启动）
louzuoen(config)#end
louzuoen#rel
（重启设备）
System configuration has been modified. Save? [yes/no]: System configuration has been modified. Save? [yes/no]: y
（保存之前的所有配置）
Building configuration...
[OK]
Proceed with reload? [confirm] 00:10:27: %SYS-5-RELOAD: Reload requested
System Bootstrap, Version 11.0(10c)XB2, PLATFORM SPECIFIC RELEASE SOFTWARE (fc1)
......
Press RETURN to get started! User Access Verification Password: louzuoen(boot)>en
（迷你模式）
Password:
louzuoen(boot)#show fla System flash directory:
File Length Name/status
1 8039948 louzuoen
[8040012 bytes used, 8737204 available, 16777216 total]
16384K bytes of processor board System flash (Read/Write)
（show flash，此时flash可读可写，因为系统从ROM中迷你的IOS启动） louzuoen(boot)#era fla
（擦除flash中的目录，模拟flash中没有IOS） System flash directory:
File Length Name/status
1 8039948 louzuoen
[8040012 bytes used, 8737204 available, 16777216 total] Erase flash device? [confirm]
Are you sure? [yes/no]: y
Erasing device... eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
（表示正在擦除）
ee ...erased
（2）执行系统还原；
louzuoen(boot)#copy tftp fla
（将tftp服务器上备份好的IOS还原到flash中） System flash directory:
No files in System flash
[0 bytes used, 16777216 available, 16777216 total]
Address or name of remote host [255.255.255.255]? 192.168.1.6
Source file name? louzuoen
（tftp服务器上的备份文件名）
Destination file name [louzuoen]?
Accessing file 'louzuoen' on 192.168.1.6...
Loading louzuoen from 192.168.1.6 (via Ethernet0): ! [OK]
（表示可以访问到指定的文件） Erase flash device before writing? [confirm] Copy 'louzuoen' from server
as 'louzuoen' into Flash WITH erase? [yes/no]y
（在还原之前，进行flash的初始化即格式化）
Erasing device... eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee
ee ...erased
Loading louzuoen from 192.168.1.6 (via Ethernet0): !!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
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!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!
[OK - 8039948/16777216 bytes]
（同样地，全部是‘!’，还原成功） Verifying checksum... OK (0x3F3D)
Flash copy took 0:03:58 [hh:mm:ss] louzuoen(boot)#conf t
Enter configuration commands, one per line. End with CNTL/Z.
louzuoen(boot)(config)#con
louzuoen(boot)(config)#config-register 0x2102
（修改寄存值，让路由器从flash中启动）
louzuoen(boot)(config)#end
louzuoen(boot)#rel
0:07:33: %SYS-5-CONFIG_I: Configured from console by console
louzuoen(boot)#rel
（重启，路由器从flash中启动）
......
Press RETURN to get started! User Access Verification Password: louzuoen>en Password:
louzuoen#show fla System flash directory:
File Length Name/status
1 8039948 louzuoen
[8040012 bytes used, 8737204 available, 16777216 total]
16384K bytes of processor board System flash (Read ONLY)
（flash只读）(责任编辑：admin) |
