You have been tasked with creating a VPC network topology for your company. The VPC network must support
both Internet-facing applications and internally-facing applications accessed only over VPN. Both Internet-facing
and internally-facing applications must be able to leverage at least three AZs for high availability. At a minimum,
how many subnets must you create within your VPC to accommodate these requirements?
A.
2
B.
3
C.
4
D.
6
D
The PUB (Public) and the PRV (Private) facing applications cannot coexist on the same subnet. That would be against all of the architecture’s and security rules. Also the scenario says “Both Internet-facing and internally-facing applications must be able to leverage at LEAST THREE Availability Zones for high availability” which means the PUB application with it’s subnet requirement (one subnet per AZ) must have footprint into all THREE AZs. That is the same for the PRV application. So the math is 3 subnets for the PUB application (1 subnet per AZ) and 3 subnets for the PRV application = 6 subnets total
the relation between subnet and availability zone is 1:1