Working With VPC Peering

A VPC peering connection is a networking connection between two VPCs that enables you to route traffic between them using private IPv4 addresses or IPv6 addresses. Instances in either VPC can communicate with each other as if they are within the same network. You can create a VPC peering connection between your own VPCs, or with a VPC in another AWS account. The VPCs can be in different regions (also known as an inter-region VPC peering connection).

• Go to VPC > Peering Connections > Create Peering Connection
• Select Requester & Accepter
  
• After peering is created you to Accept request by going Action
  

• Now we would need to make route pointing to appropriate VPC
  In our MyFirstVPC, I want only my public subnet EC2 instance to talk to default VPC EC2 over private IP, so editing Public Route Table (if you private subnet also to talk then below similar changes will be need in Private Route Table as well)
  
• Similarly for default VPC route table
  
• For testing lets create a EC2 in default VPC
  
• Rules would be needed to allowed on security
  Below example is for Public-1A-SG
  
• Similarly allowing a rule on Default VPC EC2’s security group
  
• Now try to ping private IP of default VPC EC2 from Our MyFirstVPC public EC2
  
• You delete the EC2 instances created in course of VPC lab, don’t delete the VPC as need in future Labs