Google PCA Manage and provision cloud infrastructure Practice Question

Exhibit

Refer to the exhibit.
```
$ gcloud compute instances list
NAME: web-server-1
ZONE: us-central1-a
MACHINE_TYPE: n1-standard-2
PREEMPTIBLE: true
INTERNAL_IP: 10.128.0.2
EXTERNAL_IP: 35.184.12.34
STATUS: RUNNING

NAME: web-server-2
ZONE: us-central1-b
MACHINE_TYPE: n1-standard-2
PREEMPTIBLE: false
INTERNAL_IP: 10.128.0.3
EXTERNAL_IP: 35.184.12.35
STATUS: RUNNING
```

A developer notices that web-server-1 is preemptible. They want to ensure their application remains available even if this instance is terminated. What should they do?

⚠ Common exam trap

Google Cloud often tests the misconception that a load balancer alone provides high availability, but without a managed instance group to recreate terminated instances, the load balancer has no healthy backends to route traffic to.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Create a managed instance group for web-server-1 and set an autoscaler.

A managed instance group (MIG) with an autoscaler ensures that if the preemptible instance is terminated, the MIG automatically recreates it to maintain the desired number of instances. This provides resilience against preemption by restoring capacity without manual intervention. The load balancer can then distribute traffic across healthy instances in the group.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
Modify the instance's preemptible flag to false.
Why it's wrong here
A preemptible instance's flag cannot be changed after creation; the VM must be recreated as standard or the workload moved to a managed instance group. It is tempting because flipping a setting appears to remove termination risk, which is valid only when initially provisioning a non-preemptible instance.
✓
Create a managed instance group for web-server-1 and set an autoscaler.
Why this is correct
A managed instance group replaces the single preemptible VM with multiple identical instances, so termination of one does not cause an outage. The autoscaler maintains capacity and recreates instances automatically, satisfying the availability requirement despite preemption.
✗
Create a load balancer pointing to web-server-1's external IP.
Why it's wrong here
A load balancer pointing at one instance's external IP still has a single backend; terminating that instance removes all capacity. Load balancing is tempting because it distributes traffic across backends, which is correct when the target pool contains multiple healthy instances across zones.
✗
Create a snapshot schedule for web-server-1.
Why it's wrong here
Snapshots preserve disk data for recovery, but they do not keep the application serving traffic when the instance is terminated. Snapshot schedules are tempting because they protect against data loss, which is the right control for stateful workloads needing point-in-time restore, not for maintaining availability.

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Google PCA Manage and provision cloud infrastructure Practice Question

Exhibit

Why each option matters

Option-by-option breakdown

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