1. start the tftp server, and copy firmware update version image file to tftp server.
2. press [edit] on this page.
3. tftp server: type the ip of tftp server.
4. remote file name: type the image file name.
5. press ctrl+a to go back action line.
6. press [save] key, it will start to download the image file.
7. when save successfully, the image file download finished too.
8. restart the switch.
