I just upgraded to High Sierra with the latest patches from El Capitan. I've been running El Capitan for years with both Ethernet ports working (Z170M-ITX/ac, Intel I219V + Realtek RTL8111H)
I am running the latest kext installed in /Library/Extensions
✗ kextstat | grep Real
63 0 0xffffff7f81a45000 0x67000 0x67000 com.insanelymac.RealtekRTL8111 (2.2.1) FDD47F63-B851-312E-AC10-047DCBD6708F <18 12 5 4 3 1>
The Ethernet appears (and says it's connected) in ifconfig and in the...
RTL8111H High Sierra 10.13.2 (17C205)
I am running the latest kext installed in /Library/Extensions
✗ kextstat | grep Real
63 0 0xffffff7f81a45000 0x67000 0x67000 com.insanelymac.RealtekRTL8111 (2.2.1) FDD47F63-B851-312E-AC10-047DCBD6708F <18 12 5 4 3 1>
The Ethernet appears (and says it's connected) in ifconfig and in the...
RTL8111H High Sierra 10.13.2 (17C205)