VPC Peering: Routing IPs Between Private Clouds

Introduction: The Cloud Bridge

You have a database in 'VPC Alpha' and a web server in 'VPC Beta'. Because they are in separate Virtual Private Clouds, they cannot talk to each other, even if they are in the same AWS account. To connect them without going over the public internet, you must use VPC Peering.

The Route Table Update

VPC Peering acts like a physical cable between the two networks. However, plugging the cable in isn't enough. You must update the **Route Tables** on both sides. VPC Alpha's router must be explicitly told: "If you want to reach IP range `10.2.x.x`, send the traffic over the Peering Connection."

Conclusion

VPC Peering allows massive companies to build secure, modular architectures where dozens of isolated networks talk to a central hub privately. Test internal latency between peers here.