AWS Certified CloudOps Engineer - Associate
Internet, NAT, and Egress-Only Gateways
Three devices connect a VPC to the internet, and each one exists because the other two cannot do its job. This lesson covers what an internet gateway actually translates, why NAT gateways fail in ways that look like application bugs, and why IPv6 needs a fourth answer entirely.
Intermediate 28 minutes 6 Learning Objectives
- Explain the 2 jobs an internet gateway performs and why a route to it is not enough on its own
- Compare public and private NAT gateways by the traffic each one is designed to carry
- Predict the failure modes of a zonal NAT gateway during an Availability Zone event and during a traffic spike
- Diagnose NAT gateway problems from the ErrorPortAllocation, IdleTimeoutCount, and connection-count metrics
- Choose an egress-only internet gateway over a NAT gateway based on IP version
- Identify the 2 largest sources of NAT gateway cost and the standard ways to reduce them