I had a corrupted IOS image on a 3750E switch today and feared for a xmodem transfer to eat up my day, until I found that you can copy from TFTP. It’s very well hidden, but still possible. Here’s how:
When the switch has ‘booted’ without a proper IOS, you’ll be in the ‘switch: ‘ command line. In the following example, I will assume that the TFTP server has IP 192.168.0.10 and the switch will use 192.168.0.1.
Connect your TFTP server to the ethernet management port, then follow this sequence:
switch: set IP_ADDR 192.168.0.1/255.255.255.0
switch: set DEFAULT_ROUTER 192.168.0.10
switch: copy tftp://192.168.0.10/IOS_image_file_name.bin flash:IOS_image_file_name.bin
switch: set BOOT flash:IOS_image_file_name.bin
That should do it.