NAT Gateway

• In AWS ec2 instances in private subnet are not connected to internet.
• For outbound/egress internet connectivity (one-direction), we need to use NAT (Network Adress Translations)
• AWS provides to ways of creating NAT
  • NAT Instance:
    • We create a ec2 instance with special AMI with elastic ip and configure the private route table to forward packets to ec2 instance when it needs to connect to internet
    • This is not recommended approach as we have Single Point of Failure.
  • NAT Gateway:
    • This is NAT as a Service with SLA
    • This is chargable
• Practical stuff
  • Create a vpc with two public and two private subnets
• Create an ec2 instance in public subnet and one in private subnet
• EC2 instance in public subnet can connect to internet
  
• EC2 instance in private subnet cannot connect to internet
  
• Lets create a NAT Gateway in any public subnet with elastic ip
  
  
  
• Now lets add route to private router to forward packets to NAT Gateway
  
• Now private ec2 instance should be able to connect to internet
  
• Overview
  

Exercise

• What will nord vpn do