You set up an autoscaling instance group to serve web traffic for an upcoming launch. After configuring the instance group as a backend service to an HTTP(S) load balancer, you notice that virtual machine (VM) instances are being terminated and re-launched every minute. The instances do not have a public IP address. You have verified the appropriate web response is coming from each instance using the curl command. You want to ensure the backend is configured correctly. What should you do?
A) Ensure that a firewall rules exists to allow source traffic on HTTP/HTTPS to reach the load balancer.
B) Assign a public IP to each instance and configure a firewall rule to allow the load balancer to reach the instance public IP.
C) Ensure that a firewall rule exists to allow load balancer health checks to reach the instances in the instance group.
D) Create a tag on each instance with the name of the load balancer. Configure a firewall rule with the name of the load balancer as the source and the instance tag as the destination.

Question

Quizplus · Accepted Answer

The issue is likely due to the load balancer's health checks not being able to reach the instances. Ensuring a firewall rule exists to allow health checks will prevent instances from being terminated and re-launched.

You Set Up an Autoscaling Instance Group to Serve Web