Oracle Cloud Infrastructure 2019 Developer Associate — Question 47

You are deploying a highly available web application in Oracle Cloud Infrastructure and have decided to use a public load balancer. The back-end web servers will be distributed across all three availability domains (ADs).
How many subnets should you create to deliver a secure, highly available application?

Answer options

• A. three subnets in total; one subnet in each AD
• B. five subnets in total; two subnets each in the first and second AD with a single subnet in the third AD
• C. six subnets in total; two subnets in each AD; one for the load balancer and one for the web servers
• D. four subnets in total; one subnet in each AD for the web servers and a single subnet in any one AD for the load balancer

Correct answer: C

Explanation

The correct answer is C because having two subnets in each AD allows for redundancy and load balancing, with one subnet designated for the load balancer and the other for the web servers. The other options do not provide enough subnets to separate the load balancer from the web servers effectively, which is essential for maintaining high availability and security.