Cisco IOS软件中备份和升级

　备份和升级是两个方向相反的过程。依照通常的约定，备份是指从网络设备向TFTP服务器中复制软件，而升级是指从TFTP服务器向网络设备复制软件。本文通过实验演示对Cisco路由器的IOS软件映像文件进行备份和升级。

首先启动Cisco TFTP Server，并把TFTP server root指定到目录"D:LCCNA LAB\IOS"下，保持其开启状态。

Router#sh flash

System flash directory:

File Length Name/status

1 c2501-d-1,121-8a.mz

[4289668 bytes used, 4098940 available, 8388608 total]

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

Router#copy flash tftp

Source filename []? c2500-d-1.121-8a.mz

Address or name of remote host []? 172.16.162.58

Destination filename [c2500-d-1.121-8a.mz]? (按回车键确认)

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!

4289602 bytes copied m 62.320 secs (69187 bytes/sec)

Router#

Router#copy tftp flash

Address or name of remote host []? 172.16.16258

Source filename []? c2500-d-1.121-8a.mz

Destination filename [c2500-d-1.121-8a.mz]? (按回车键确认)

%Waming:There is a file already existing with this name

Do you want to over write? [confirm] (按回车键确认)

Accessing tftp://172.16.162.58/c2500-d-1.121-8a.mz...

Erase flash: befeor copying?[confirm] (按回车键确认)

Erasing the flash filesystem will remove all files! Continue? [confirm] (按回车键确认)

Erasing.device...eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee...erased

Erase of flash:complete

Loading c2500-d-1.121-8a.mz from 172.16.162.58(via

Ethernet0):!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

!!!!!!!!!!!!!!!!!!!!!!

[OK-4289602/8579072bytes]

Verifying checksum,.. OK(OxC766)

4289602 bytes copied in 100.896secs(42896bytes/sec)

Router#reload

Proceed with reload? [confirm] (按回车键确认)

13:41:30: %SYS-5-RELOAD: Reload requested

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

Copyright (c) 1986-1995 by cisco Systems

(1)用sh flash命令查看flash中的IOS文件名，以便进行下一步操作。

(2)使用copy flash tftp命令从flash向TFTP服务器备份IOS软件映像，根据提示依次键入源文件名(Flash中的IOS文件名)。TFTP服务器的IP地址(或主机名)以及目标文件名(可用与源文件相同的缺省文件名、如果使用主机名则路由器上必须配置主机表或启用DNS查找功能，使路由器通过主机名查找到TFTP服务器。一系列的"!"表示传输正常进行，文件复制完成后路由器报出文件长度、所用时间和每秒复制字节数的信息，表明备份过程顺利结束。

(3)用copy tftp flash向路由器中升级IOS软件时，与备份时相似需要键入TFTP服务器名、源文件(TFTP服务器上的文件)名、目标文件名 (复制到Flash中的文件名)。

系统提示是否在拷贝之前将Flash中的文件系统删除，按回车键确认后系统再次提示删除操作将把Flash中的所有文件清除，问是否继续，再次按回车键确认删除操作。一系列的"e"表示正在进行删除Flash上文件系统的操作。接下来是文件复制的进程，同样以一系列的"!"来表示，"!"的数目越多表示文件越大。

最后系统对IOS文件进行了校验，并确认传输没有错误，IOS软件升级操作即告完成。

IOS软件升级完成后，需要重新启动路由器，使得新软件进入运行状态。应该注意的是，IOS软件的升级对存放在NVRAM中的启动配置文件并不产生任何影响，路由器的启动配置文件还是原来的文件。