AWS VPC best practices
VPC is the foundation of your cloud architecture, don't let small mistakes cost you big.
What’s VPC?
A VPC is the foundation of cloud environments, which provides a secure and isolated network space where different resources can be deployed.
By following the best practices, organizations can advance resource usage, improve network performance, and moderate potential security risks.
1. Configure the right CIDR block
The CIDR block also determines the size of the subnet.
if you choose the wrong IP ranges, your app will face conflicts, restrictions, and a painful rework when it scales.
Pick a /16 CIDR block like 10.0.0.0/16.
This will give you 65,536 IP addresses and a lot of space.
Split production into /24 subnets, each with 256 IP addresses.
Use /26 subnets with 64 IP addresses for development and testing.
2. Segment Subnets Effectively
Subnet splits your VPC into zones for different resources, adding security and scalability.
Place your web servers in public subnets across multiple AZs.
Deploy internal app servers in private subnets and use an ALB in public subnets.
3. Connect VPC across regions
Cross-region VPC connections allow secure, private communication between environments in different locations, essential for:
Disaster Recovery: In case of a regional outage, you can failover your applications to a different region and maintain business continuity.
Global Reach: Serve customers in different geographical locations with lower latency by hosting resources closer to them.
Data Replication and Backup: Replicate data across regions for backup and disaster recovery purposes.
Shared Services: Centralize certain services like logging, monitoring, or security in one region and make them accessible to other regions.
4. Secure Your VPC groups
Security Groups and Network ACLs (NACLs) are your gatekeepers.
Together, they create layers of access control to shield your resources from unwanted traffic.
Limit inbound connections to only your application subnets on port 3306 for databases.
Set up Security Groups to allow web traffic on port 80
Restrict SSH (port 22) access to specific IPs.
5. Set up a Bastion to access your resources
You might need an SSH Bastion to access your resources once they are isolated from the Internet.
A bastion is a dedicated server that provides a secure access point with strong authentication and access control, allowing you to access the resources behind it.
To create a Bastion Host Instance:
Launch an EC2 instance: Choose an Amazon Machine Image like Amazon Linux 2 or Ubuntu. A
t2.microinstance type is often sufficient for basic bastion host functionality.Place it in a public subnet: Ensure the instance is launched within a subnet that has a route to the internet via an Internet Gateway.
Assign a public IP address: This allows you to connect to the bastion host from your local machine.
Lastly,
Designing a VPC on AWS with best practices is essential for accomplishing ideal execution, security, and scalability in cloud architectures.
By observing the guidelines mentioned, organizations can ensure their VPCs are robust and well-architected.