Linux IPSec with IKEv2 Setup

The following Strogswan configuration is known to work

1. Create a config file in your strongswan ipsec.d directory e.g. ivpn.conf with the following

   conn ivpn
       keyexchange=ikev2
       right=gb.gw.ivpn.net
       rightid=gb.gw.ivpn.net
       rightsubnet=0.0.0.0/0
       rightauth=pubkey
       leftsourceip=%config
       leftauth=eap-mschapv2
       eap_identity=ivpnUserName
       auto=start
       dpdaction=restart

   Change the right= and rightid= as appropriate for the server you want to connect to.
2. Create a .secrets file e.g. ivpn.secrets in the strongswan ipsec.d directory e.g. ivpn.secrets with the following

   ivpnUserName : EAP "YourPassWord"

   Note that there is a space either side of the colon :.
3. You may need to download this CA certificate and store it in a file located in your strongswan ipsec.d/cacerts directory.
4. Tell strongswan to restart or reload it's config.