We had a weird issue few days ago, with a compact UTM based on Intel Celeron N3350 on board.

When installing Ubuntu, the onboard network card Intel I211 were not working at all. In syslog and dmesg we could see a kernel dump and then, when network was accessed, the card was continuously being reset.

[  113.061802] igb 0000:06:00.0 enp6s0: igb: enp1s0 NIC Link is Down
[  113.924585] igb 0000:06:00.0 enp6s0: Reset adapter
[  115.633067] igb 0000:06:00.0 enp6s0: igb: enp1s0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: RX/TX

After long we found out to be a bios setting: in advanced settings, OS installation, we had to choose Intel as operating system. After doing this we were finally able to install Ubuntu and use networking.

What is weird that only Linux was affected by the problem. In fact trying with OPNsense or pfSense the Intel I211 cards were working perfectly! Just Ubuntu was unable to use them.

We had tried all sort of workaround, even disabling all the available hardware features of the network card.