1.备份IOS和配置文件
1.首先要有一个配置好的ftp服务器，并且保证要在一个网段中（能够互相的ping通）。
实例：
Switch#copy flash: tftp:
Source filename []? c2960-lanbase-mz.122-25.FX.bin
Address or name of remote host []? 192.168.1.2
Destination filename [c2960-lanbase-mz.122-25.FX.bin]?
Writing c2960-lanbase-mz.122-
25.FX.bin...!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!
[OK - 4414921 bytes]
4414921 bytes copied in 0.281 secs (426881 bytes/sec)
这样就将一个IOS备份到了ftp服务器上，这个可以对IOS的升级和重装提供便利。
2.恢复IOS和配置文件
实例：
Switch#copy tftp flash:
Address or name of remote host []? 192.168.1.2
Source filename []? c2960-lanbase-mz.122-25.FX.bin
Destination filename [c2960-lanbase-mz.122-25.FX.bin]?
%Warning:There is a file already existing with this name
Do you want to over write? [confirm]
Accessing tftp://192.168.1.2/c2960-lanbase-mz.122-25.FX.bin....
Loading c2960-lanbase-mz.122-25.FX.bin from 192.168.1.2:
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
[OK - 4414921 bytes]
4414921 bytes copied in 3.313 secs (36206 bytes/sec)