C. A multivalue answer routing policy in Route 53 allows you to configure multiple values for a DNS record, and Route 53 responds to DNS queries with multiple random values. This enables the distribution of traffic randomly among the available EC2 instances. E. By launching EC2 instances in different AZs, you achieve high availability and fault tolerance. Launching four instances (two in each AZ) ensures that there are enough resources to handle the traffic load and maintain the desired level of availability. A. Failover routing is designed to direct traffic to a backup resource or secondary location only when the primary resource or location is unavailable. B. Although a weighted routing policy allows you to distribute traffic across multiple EC2 instances, it does not ensure random distribution. D. While launching instances in multiple AZs is important for fault tolerance, having only three instances does not provide an even distribution of traffic. With only three instances, the traffic may not be evenly distributed, potentially leading to imbalanced resource utilization.

I went back and rewatched the lectures from Udemy on Weighted and Multi-Value. The lecturer said that Multi-value is *not* as substitute for ELB and he stated that DNS load balancing is a good use case for Weighted routing policies

CE is correct

CE seems good to me due to " highly available and fault tolerant" and following explanation: https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-policy-multivalue.html

E: For HA C: Random routing can only be created with multivalue answer routing policy. https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-policy-multivalue.html "To route traffic approximately randomly to multiple resources, such as web servers, you create one multivalue answer record for each resource and, optionally, associate a Route 53 health check with each record. "

C. A multivalue answer routing policy in Route 53 allows you to configure multiple values for a DNS record, and Route 53 responds to DNS queries with multiple random values. This enables the distribution of traffic randomly among the available EC2 instances. E. By launching EC2 instances in different AZs, you achieve high availability and fault tolerance. Launching four instances (two in each AZ) ensures that there are enough resources to handle the traffic load and maintain the desired level of availability. A. Failover routing is designed to direct traffic to a backup resource or secondary location only when the primary resource or location is unavailable. B. Although a weighted routing policy allows you to distribute traffic across multiple EC2 instances, it does not ensure random distribution.

First I thought it was weighted but after research C is the correct answer : https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-policy.html

Multivalue routing can do random load balancing according to the AWS website: To route traffic approximately randomly to multiple resources, such as web servers, you create one multivalue answer record for each resource and, optionally, associate a Route 53 health check with each record. https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-policy-multivalue.html

This questions is so wired , 3 instances nothing wrong with it

Option CE Correct: To route traffic roughly and randomly to multiple resources, such as web servers, you create a multi-value response record for each resource and optionally associate a Route 53 health check with each record. https://disaster-recovery.workshop.aws/en/services/networking/route53/routing-policies/routing-multiple-answer.html

CE is correct

Highly available and fault tolerant = two instances in two AZs Route traffic randomly = Amazon Route 53 multivalue answer routing policy

Multivalue answer routing policy – Use when you want Route 53 to respond to DNS queries with up to eight healthy records selected at random. You can use multivalue answer routing to create records in a private hosted zone. Weighted routing policy – Use to route traffic to multiple resources in proportions that you specify. You can use weighted routing to create records in a private hosted zone.

I chose CE, but couldn't it also be BE? If you set all of the weights to the same, equal value? Wouldn't then the traffic be distributed randomly and evenly among all healthy instances?

Randomly is the key word

C: Multi-value To route traffic approximately randomly to multiple resources and have healt check B: Weighted default use for when you need load to one server more than ohter server. if you need for random to all server should be letter in this C options "and weight to all server with same value".

Must C and E, B is not correct because it based on the assigned weight it can not do randomly