2960X救砖方法

 注意那个冒号和斜杠，还有空格，格式要绝对正确，在这个模式下tftp是单向的,只能下载，不能上传，还有，源文件名和目标文件名必须相同，血的教训阿。。。

Initialize the flash:
switch: flash_init

Initialize the management interface:（这一步好像没必要）
switch: mgmt_init

Then assign an IP address to the management interface:
switch: set IP_ADDR 10.1.100.2/255.255.255.0
switch: set DEFAULT_ROUTER 10.1.100.1

Then configure your TFTP server to have an IP on the same subnet and connect it to the management interface of the switch (ie 10.1.100.1/24)

Now to tell the switch to retrieve the firmware image:(这一步前有些机器要做 fsck flash:)
switch: copy tftp://10.1.100.1/c2960x-universalk9-mz.152-5b.E.bin flash:c2960x-universalk9-mz.152-5b.E.bin

The switch should then retrieve the image and save it flash.

Once the copy is complete boot from it with:

switch: boot flash:c2960x-universalk9-mz.152-5b.E.bin

然后可以直接重启，或者重新设定boot变量的值