Ethernet port is associated to <code>eth0</code> interface on the J8 connector. It can be managed with standard Linux commands. See for example http://www.tecmint.com/ifconfig-command-examples/.
=== LED ===
The two LEDs, connected to the ethernet PHY are configured as ''Tri-color dual-LED mode'' (see more info in the [https://ww1.microchip.com/downloads/en/DeviceDoc/00002117F.pdf#page=24 KSZ9031 datasheet])