Huawei Ont Firmware Flash Tool Link

A: Flashing generic firmware removes ISP customizations, but the ONT still must be registered with the OLT via its serial number (SN) and password. That’s a separate process.

The most common tool erroneously called the "flash tool" is (e.g., ONTUpgradeTool_V300R016C00SPC001.exe ). huawei ont firmware flash tool

TFTP/FTP via bootloader or recovery