Exam AWS Certified Solutions Architect - Associate SAA-C03 topic 1 question 70 discussion

I would choose A, as NLB supports HTTP and HTTPS Health Checks, BUT you can't put any URL (as proposed), only the node IP addresses. So, the solution is C.

Option C. NLB works at Layer 4 so it does not support HTTP/HTTPS. The replacement for the ALB is the best choice.

Ans C - Yup, somethings happening at the Application level so replace NLB with ALB

NLB is for network errors and low level traffic stuff ALB is for application so C is the only realistic option here

NLB does support HTTP/HTTPS Health Checks. I saw other people comments, it seems like the question were rephrased. The comments were highlighting "application URL", but I don't see words on the question.

You can use HTTP/HTTPS ONLY when Target is ALB. By default it is TCP. https://docs.aws.amazon.com/elasticloadbalancing/latest/network/target-group-health-checks.html#health-check-settings HealthCheckProtocol The protocol the load balancer uses when performing health checks on targets. The possible protocols are HTTP, HTTPS, and TCP. The default is the TCP protocol. If the target type is ALB, the supported health check protocols are HTTP and HTTPS.

ALB allows you to specify the path which helps to check the error. NLB cannot do that.

The key points are: Use an Application Load Balancer (ALB) instead of a Network Load Balancer (NLB) since ALBs support HTTP health checks. Configure HTTP health checks on the ALB to monitor the application health. Use an Auto Scaling action triggered by the ALB health checks to automatically replace unhealthy instances.

Option C is the right answer.

A. NLB, but NLB's health checks are designed for TCP/UDP protocols and lack the advanced features specific to HTTP applications provided by ALB. B. This approach involves custom scripting and manual intervention, which contradicts the requirement of not writing custom scripts or code. D. Since the NLB does not detect HTTP errors, relying solely on the UnhealthyHostCount metric may not accurately capture the health of the application instances. Therefore, C is the recommended choice for improving the application's availability without custom scripting or code. By replacing the NLB with an ALB, enabling HTTP health checks, and configuring Auto Scaling to replace unhealthy instances, the company can ensure that only healthy instances are serving traffic, enhancing the application's availability automatically.

Replace the NLB (layer 4 udp and tcp) with an Application Load Balancer - ALB (layer 7) supports http and https requests.

must be C Application availability: NLB cannot assure the availability of the application. This is because it bases its decisions solely on network and TCP-layer variables and has no awareness of the application at all. Generally, NLB determines availability based on the ability of a server to respond to ICMP ping or to correctly complete the three-way TCP handshake. ALB goes much deeper and is capable of determining availability based on not only a successful HTTP GET of a particular page but also the verification that the content is as was expected based on the input parameters.

Answer is C A solution architect can use Amazon EC2 Auto Scaling health checks to automatically detect and replace unhealthy instances in the EC2 Auto Scaling group. The health checks can be configured to check the HTTP errors returned by the application and terminate the unhealthy instances. This will ensure that the application's availability is improved, without requiring custom scripts or code.

I will go with A as Network load balancer supports HTTP and HTTPS health checks, maybe the answer is outdated.

https://medium.com/awesome-cloud/aws-difference-between-application-load-balancer-and-network-load-balancer-cb8b6cd296a4 As NLB does not support HTTP health checks, you can only use ALB to do so.

Answer is C, and A is wrong because In NLB, for HTTP or HTTPS health check requests, the host header contains the IP address of the load balancer node and the listener port, not the IP address of the target and the health check port. https://docs.aws.amazon.com/elasticloadbalancing/latest/network/target-group-health-checks.html

Correct answer - C Network load balancers (Layer 4) allow to: • Forward TCP & UDP traffic to your instances • Handle millions of request per seconds • Less latency ~100 ms (vs 400 ms for ALB) Best choice for HTTP traffic - replace to Application load balancer