NETWORK: I have a private subnet and a public subnet. A VPC with IG attached. There is a NAT Gateway in the public subnet. I also have 2 route table, the public route table routes everything to the IG, the private route table routes everything to the NAT Gateway.
EC2: My EC2 Windows instance is in the private subnet with a EIP and a Public DNS. It has a security group that allows all fron internet inbound/outbound but i cant even ping neither rdp
All the machine or instances in the private subnet cannot be connected externally hence the name private subnet. If you want to connect to your instance externally you must place it in the public subnet (the subnet that is connected to the internet gateway). Eventhough, you attach an elastic ip (which is a public ip) but it is routed through a NAT. The EIP must go through the internet gateway only.
If you really want to connect you need to VPN to your VPC (using AWS VPC VPN) and then RDP to your instance. Or have a gate instance in your public subnet.
Verify that the route table for the subnet has a route that sends all traffic destined outside the VPC to the internet gateway for the VPC. For more information, see Creating a Custom Route Table (Internet Gateways) in the Amazon VPC User Guide.
