cfn-vpn is a wrapper around AWS Client-VPN to improve the management experience of the VPN. The tool utilises Cloudformation to manage the AWS resources required by the Client-VPN and automates the certificate management process with the openvpn/easy-rsa library.
For further AWS documentation please visit https://docs.aws.amazon.com/vpn/latest/clientvpn-admin/scenario.html
Split tunnel when enabled will only push the routes defined on the client vpn. This is useful if you only want to push routes from your vpc through the vpn.
This can be setup with default options selected. This will push all routes from through the vpn including all internet traffic. The ENI attached to the vpn client attaches a public IP which is used for natting between the vpn and the internet. This must be placed inside a public subnet with a internet gateway attached to the vpc. Please read the AWS documentation for troubleshooting any networking issues
This is the same as above but the vpn attached to a subnet in a private subnet with the public route being routed through a nat gateway. NOTE the dns on the vpn must be set to the dns server of the vpc you've attached the vpn to, the reserved IP address at the base of the VPC IPv4 network range plus two. For example if you VPC cidr is 10.0.0.0/16 then the dns server for that vpc is 10.0.0.2.
cfn-vpn init myvpn --bucket mybucket --server-cn myvpn.domain.tld --subnet-id subnet-123456ab --dns-servers 10.0.0.2If you are experiencing issue connecting to the internet check to see if your local dns configurations are overriding the ones set by the vpn. You can test this by using dig to query a domain from the vpc dns server. For example:
dig @10.0.0.2 google.comcfn-vpn supports certificate, federated and active directory type authentication for AWS Client-VPN.
For further information on the authentication types please visit https://docs.aws.amazon.com/vpn/latest/clientvpn-admin/client-authentication.html