When the system starts the BootROM, press CTRL+B or CTRL+E within 3 seconds and then enter the default password to enter the BootROM menu.
When a chassis switch runs a version earlier than V100R006C03, the default BootROM password is 9300. When a chassis switch runs V100R006C03 or later, the default BootROM password is Admin@huawei.com.
The password may be huawei on a device that has been upgraded to the current version from an earlier one.