如果用户口令丢失，可以进入boot菜单：

    boot menu

    1. download application file to flash

    2. select application file to boot

    3. display all files in flash

    4. delete file from flash

    5. modify bootrom password

    6. enter bootrom upgrade menu

    7. skip current configuration file

    8. set bootrom password recovery

    9. set switch startup mode

    0. reboot

    enter your choice(0-9):

    选择7，然后重新启动交换机，系统启动后，用户密码会被删除。