How to set up L2TP/IPsec VPN?

Question

VPN

I created a connection via vpn according to the instructions
In the logs sudo journalctl -f I get an
error VPN connection: failed to connect: 'couldn't look up L2TP VPN gateway IP address
What do I need to enable or disable to make the connection work?'I have linux mint 18.3

Answer 1

and what do you say
couldn't look up L2TP VPN gateway IP address
ping is there and the machine is stupid?
DNS set up there or write IP