AZ-700 Question 181
Single answerYou have deployed two virtual machines (VMs) in the same virtual network subnet, both hosting an HTTP-based web application on port 80. You also created a Standard Public Load Balancer with one Frontend IP configuration. You now need to implement a load balancing rule to distribute incoming HTTP traffic on port 80 to both VMs and ensure that unhealthy instances are automatically excluded from receiving new requests. Which configuration will achieve this goal?
- A
Create and associate a health probe on port 80 and configure the load balancing rule with protocol TCP, front-end port 80, and back-end port 80.
- B
Set a health probe on port 443 and configure the load balancing rule to forward port 80 traffic to port 443 in the back-end pool.
- C
Enable Floating IP, set an idle time-out of 30 minutes on the load balancing rule, and omit the health probe to reduce overhead.
- D
Use an Application Gateway instead of a Load Balancer to create a rule that sends HTTPS traffic to port 80 on each VM.
Show answer and explanation
Correct answer: A
Explanation
When creating a load balancing rule in Azure, you must specify a front-end IP configuration, the port that external clients connect to, the matching back-end port on the VMs, and an appropriate health probe. In this scenario, both VMs listen on port 80, so forwarding traffic from front-end port 80 to back-end port 80 is required. A health probe on port 80 ensures that the load balancer can periodically check each VM� status and stop routing traffic to any unresponsive instance. For detailed guidance, refer to the official Microsoft documentation on �Create a public Standard Load Balancer� (https://learn.microsoft.com/azure/load-balancer/load-balancer-overview).
- A. Correct.
Correct. Associating an HTTP or TCP health probe on port 80 ensures the load balancer can detect if a VM stops responding. Mapping front-end port 80 to the same back-end port 80 distributes incoming HTTP traffic correctly between the VMs.
- B. Incorrect.
Incorrect. Setting the health probe to port 443 and forwarding from port 80 to 443 does not match the application� actual listening port, potentially causing failures if the VMs are not configured to accept HTTPS traffic internally.
- C. Incorrect.
Incorrect. Floating IP is typically used for scenarios like SQL Always On or NVAs that require direct IP transfer. Also, not using a health probe means the load balancer cannot detect unhealthy instances, which contradicts the requirement.
- D. Incorrect.
Incorrect. While Application Gateway can handle Layer 7 traffic, the requirement specifically mentions using a Standard Public Load Balancer for HTTP workload distribution. Switching to Application Gateway is a different service and not necessary for this scenario.