Exam AWS Certified SysOps Administrator - Associate topic 1 question 288 discussion

To route domain traffic to an ELB load balancer, use Amazon Route 53 to create an alias record that points to your load balancer. An alias record is a Route 53 extension to DNS. It's similar to a CNAME record, but you can create an alias record both for the root domain, such as example.com, and for subdomains, such as www.example.com. (You can create CNAME records only for subdomains.) https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-to-elb-load-balancer.html

https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/routing-to-elb-load-balancer.html

Typo A, B - - wrong, - there is no such a thing as IP address for ALB, as it's hidden for user and you only have an ALB DNS name, therefore it's not A&B.

You are correct that an A record typically points to an IP address. However, in the case of an Application Load Balancer (ALB), you cannot use an A record with an IP address because the IP addresses of an ALB can change over time. Instead, you can use an alias record to point to the DNS name of the ALB. An alias record is a Route 53 extension to DNS that allows you to route traffic to selected AWS resources, such as an ALB, by using a friendly DNS name, such as example.com, instead of the resource’s IP address or DNS name. Therefore, the correct answers are CD.

I think it is B, not A. Recently I needed to point a domain apex to an Application Load Balancer created in an AWS environment. The only problem here was that the domain apex or root domain cannot point to an Application Load Balancer’s endpoint. If we talk about in terms of DNS records, we cannot add a CNAME record against the apex. We can map an IP address to the apex as an A record. So, all we needed was a static IP address for our load balancer which we could map to our root domain and point it to the Load Balancer. The small issue was that Application Load Balancer does not have static IP addresses. So, I looked for methods to assign a static IP (elastic IP) address to the load balancer and found an AWS service named Global Accelerator which made it super-easy to assign static IP to the load balancer. Ref link: https://kavishbaghel.com/how-to-point-domain-apex-to-an-application-load-balancer-88a7b82d19e9