Amazon VPC Basics

What is a VPC?

An Amazon Virtual Private Cloud (VPC) is a logically isolated section of the AWS cloud where you can define and control a virtual network that you can launch AWS resources in. It provides you with complete control over your virtual networking environment, including selection of your IP address range, creation of subnets, and configuration of route tables and network gateways.

VPC Components

Subnets: Segments of a VPC's IP address range where you can place groups of isolated resources.
Route Tables: Used to determine where network traffic is directed.
Internet Gateway: A horizontally scaled, redundant component that allows communication between instances in your VPC and the internet.
NAT Gateway: Allows instances in a private subnet to connect to the internet while preventing the internet from initiating connections with those instances.

Creating a VPC

To create a VPC, follow these steps:

1. Log in to the AWS Management Console.
2. Navigate to the VPC dashboard.
3. Click on "Create VPC".
4. Enter a name and CIDR block (e.g., 10.0.0.0/16).
5. Select "Create".
6. Configure subnets and route tables as needed.

Best Practices

When working with VPCs, consider the following best practices:

Use multiple subnets for high availability.
Implement security groups and network ACLs for enhanced security.
Monitor your VPC traffic using VPC Flow Logs.
Utilize private subnets for resources that do not require direct internet access.

FAQ

What is the default size of a VPC?

The default size of a VPC is a /16 CIDR block, which provides 65,536 private IPv4 addresses.

Can I connect my VPC to my on-premises network?

Yes, you can connect your VPC to your on-premises network using AWS Direct Connect or a VPN connection.

What are VPC Peering Connections?

VPC Peering Connections allow you to route traffic between two VPCs using private IPv4 addresses or IPv6 addresses. This can be within the same AWS region or across different regions.

Flowchart: Creating a VPC

graph TD;
                A[Start] --> B[Log in to AWS Console]
                B --> C[Navigate to VPC Dashboard]
                C --> D[Click "Create VPC"]
                D --> E[Enter Name and CIDR Block]
                E --> F[Click "Create"]
                F --> G[Configure Subnets and Route Tables]
                G --> H[End];