Hey everyone! I'm facing some issues with setting up VPC Peering. I have two VPCs: VPC A has an application (RDS and EC2), and VPC B only has EC2 instances. I need VPC B to access the RDS in VPC A. I've created route tables for both the RDS subnets and the EC2 subnets, and they both reference the VPC peering connection. I can ping and SSH from EC2 in VPC A to EC2 in VPC B and vice versa, but I can't connect to the RDS. I've allowed inbound access on the RDS security group for the VPC CIDR range (10.0.0.0/16), but the connection to RDS still fails. I'm looking for advice on what I might be missing!
4 Answers
You've set everything up logically, but there's a chance that something's not configured as you think it is. You could use AWS's Reachability Analyzer to see what might be failing in the path to your RDS.
It sounds like your VPC peering connection is working since EC2-to-EC2 communication is fine. Have you checked if the subnet of your RDS is associated with the correct routing table? Also, make sure the RDS security group allows connections from the other VPC.
Totally agree! Don't forget to check DNS settings as well, just in case.
I think this could be something simple. VPC Flow Logs can help you debug this by showing you where the connection might be failing.
Also, keep in mind that the RDS security group definitely needs to permit access from VPC B. You might want to double-check those rules just to be safe.
Exactly! Routing and security groups are crucial here. If either of those isn't set up right, you won't be able to connect to your RDS.