I've got a WiFi (en0) and Ethernet (en8) connection on my machine. Each interface is on a separate network and en0 has priority over en8.
The gateway for en0 is
192.168.100.1 and for en8 it is
There are services I need to access that are only available on the en0 network, and the VPN is only available via en2 network.
I want to be able to force the macOS Sierra L2TP client to use en8. I have successfully added a static route to route the IP address that I want to connect to, to the gateway of en2 and have verified by running
trace get <vpn address>
However the connection still fails and when I look at the logs in
/var/ppp/ppp.log it looks like the L2TP client is still trying to go through the en0 gateway:
Wed Mar 22 13:53:10 2017 : l2tp_get_router_address 192.168.100.1 from dict 1