Internet Connectivity for Private subnets

• The Basic NAT Server Overview
  
• With respect to AWS, we can create a NAT Server in a public subnet with public ip and configure the private route table to forward the packets to NAT server whenever they have to connect to internet.
• In AWS To Create a NAT Server, we have two ways
  • NAT Instance:
    • We would create an ec2 instance in public subnet with NAT AMI (Image)
  • Managed NAT (NAT Gateway):
    • This is a Managed Service, AWS will Scale it and Ensure the NAT Gateway is highly available
    • This is a chargable service.
      
• We would be using the NAT Gateway
  
  
  
  
• Now NAT Gateway is created in the public ip, now we need to configure the private route table’s route to forward the internet traffic to NAT Gateway.
  
  
  
  
• Now the ec2 instances in private subnet should have internet connectivity.
  
• Note: Please remove all the resources after usage
  • NAT Gateway => Hourly charges
  • Public IP => Elastic IP

AWS Architecture Diagrams

• Refer Here for the architecture icons
  
• Sample Architecture Diagram in Visual Paradigm