In this section, we explore how to provide internet access to subnets within an AWS Virtual Private Cloud (VPC). Understanding the distinction between Public and Private Subnets is essential, as well as the role of an Internet Gateway (IGW) in enabling internet connectivity. Here's a simplified breakdown:
Internet Gateway (IGW)
- Purpose: Allows resources within a VPC, like EC2 instances, to connect to the internet.
- Characteristics:
- Scales horizontally, ensuring it can handle varying loads.
- Highly available and redundant, offering reliable connectivity.
- Configuration:
- Must be created separately and then attached to a VPC.
- A one-to-one relationship exists between a VPC and an IGW.
Subnets and Internet Access
- Initially, subnets within a VPC do not have internet access.
- Public Subnet vs. Private Subnet:
- Public Subnet: Intended to house resources that need to connect to the internet.
- Private Subnet: Used for resources that do not require direct internet access.
Enabling Internet Access
- Create an Internet Gateway and attach it to your VPC.
- Modify Route Tables:
- To enable internet access, you must edit the VPC's route tables to direct traffic to the IGW.
This setup ensures that EC2 instances within the Public Subnet can reach the internet via the Route Table's direction to the IGW, thereby enabling connectivity to external networks.
In the upcoming lecture, we'll delve deeper into the technical steps involved in this process, providing a hands-on approach to configuring internet access within a VPC.