We want to install Ubuntu on an industrial computer. After installation, COM, DIO and the watchdog do not work. What should we do?

Common components such as the CPU, Intel network controllers, USB and SSD usually work out of the box on a recent Ubuntu LTS. What is often missing is vendor-specific hardware: DIO, watchdog, hardware sensors, RS-485 mode, and sometimes Panel PC backlight and touch. How to proceed: 1. Look up the vendor's supported operating systems for the exact model, which usually list tested Ubuntu and kernel versions. Install that version if possible. 2. Download the vendor's Linux driver package or library for DIO and watchdog. Many vendors ship source code to compile against your kernel, so a kernel update may require recompiling. 3. COM ports: check the ttyS devices listed by the system; RS-232/485 mode is usually set in BIOS before the operating system loads. 4. Very new network or Wi-Fi chips may not be recognised on an older kernel and need a newer one. Test every port you need on a sample machine before cloning for the whole project, and pin the kernel version once the system is stable.