The upgrade process follows a strict linear progression to ensure system integrity:
To upgrade your device firmware to version 12.5.5 (or a related build like 12.5.1 SU6) using i tftp upgrade firmware version 1255 download install
This blog post outlines how to download and install firmware version 1255 using the Trivial File Transfer Protocol (TFTP), a standard method for recovering or manually updating network hardware. Guide: Installing Firmware Version 1255 via TFTP The upgrade process follows a strict linear progression