1. Place the switch OS firmware file (which has "stk" as the filename extension) to a tftp server to which the switch can access
2. Run the following CLI on the switch
copy tftp://<TFTP_SERVER_IP>/<PATH>/<FIRMWARE_FILE_NAME> backup
3. Type y
when the following is displayed
Are you sure you want to start? (y/n) y
4. If file transfer is successful, the following will be displayed
File transfer operation completed successfully.
5. Type the following commands to reboot the switch
boot system backup
6. Type reload
to reboot the switch
Activating image backup ..
Are you sure you want to reload the stack? (y/n) y
Reference platform resetting ...