How do I troubleshoot IKEv2 VPN issues on El Capitan?
I've followed these instructions to create an IKEv2 VPN (and certificate) on a Ubuntu server that I want to connect to, which all seems pretty reasonable.
I'm now trying to connect to it from my Mac. I've created an IKEv2 connection with (what I think are) the appropriate details. When I click connect, the VPN menu icon just shows the connecting lights for 2 minutes but nothing happens. There is no output (error or otherwise) in /var/log/system.log or on syslog -w. There is no error message or evidence of any sort of connection attempt on the server. If I change the server address in the VPN config to something non existent, the results are identical, so clearly it's not really doing anything useful.
How do I find out what it actually thinks it's doing though? Surely something should be getting logged somewhere. I have tried adding
log debug;
path logfile "/var/log/racoon.log";
to /etc/racoon/racoon.conf and restarting but I still get nothing.
Update - I'm now getting some error output (post reboot):
Oct 12 21:27:06 testing nesessionmanager[519] <Notice>: NESMIKEv2VPNSession[VPN (IKEv2):930E0F86-1878-42E5-9CBD-08FD10677429]: Received a start command from SystemUIServer[415]
Oct 12 21:27:06 testing nesessionmanager[519] <Notice>: NESMIKEv2VPNSession[VPN (IKEv2):930E0F86-1878-42E5-9CBD-08FD10677429]: status changed to connecting
Oct 12 21:27:06 testing nesessionmanager[519] <Error>: Failed to find the VPN app for plugin type com.apple.neplugin.IKEv2
...
Oct 12 21:29:06 testing nesessionmanager[519] <Notice>: NESMIKEv2VPNSession[VPN (IKEv2):930E0F86-1878-42E5-9CBD-08FD10677429]: status changed to disconnecting
Oct 12 21:29:06 testing nesessionmanager[519] <Notice>: NESMIKEv2VPNSession[VPN (IKEv2):930E0F86-1878-42E5-9CBD-08FD10677429]: status changed to disconnected, last stop reason Tunnel did not come up in time
