What is an Internet Gateway?
An Internet Gateway is redundant, horizontally scaled, and a highly available VPC component. It allows communication between instances in your VPC and the internet using VPC route tables for internet-routable traffic.
An Internet Gateway supports IPv4 and IPv6 traffic. It does not cause availability risks or bandwidth constraints on your network traffic.
Only one Internet Gateway can be attached per VPC. There is no additional cost for having an Internet Gateway in your account.
Rules to enable access an EC2 instance from the internet
- Create an Internet Gateway and attach it to your VPC.
- Ensure that instances in your subnet have either a public IP address or an elastic IP address.
- Add your subnet’s route table to the Internet Gateway.
- Ensure that your security group and network access control lists (NACL) allow relevant traffic to flow in and out of your instance.