Level 4: Reliability, security & cloud · L4.6 AWS architecture decisions (SAA-C03)
VPC anatomy: subnets, routes, NAT and two firewalls
Lay out a two-zone VPC with public and private subnets, route tables and NAT gateways, and choose between security groups and network ACLs for a rule.
13 min · Pro
What you take away
- A subnet is public only because its route table sends 0.0.0.0/0 to an internet gateway; private subnets send it to a NAT gateway, which lets traffic out but never lets a connection in.
And 3 more inside the class, in Pro.
How the class is laid out
- The problem
- The simple version
- Public is a route, not a label
- Two firewalls, two jobs
- Check your understanding