Could you check for “Setting Up Networking on the Host and Target” Section your topic in Drive OS documentation.(NVIDIA_DRIVE_SW_8.0_References/DRIVE_Software/index.html#page/DRIVE%2520Linux%2520Software%2520SDK%2520Development%2520Guide%2FNetwork%2520Setup%2Fnetwork_setup.html%23)
Can you please attach a picture to show your Host and board connection, ifconfig output in detail to understand the issue in better way. I assume you have flashed board with Drive 8.0.
Just for clarification, when you connect your board to internet via 10Gbe port, you notice change in br0 value. Please check that.