Compute commands (instances, disks) in GCP - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ service_behavior

intermediate

What is the result of this command?

You run the command to list all VM instances in a project:

gcloud compute instances list --filter="zone:(us-central1-a)"

What will this command output?

A A list of all VM instances in all zones of the project.

B A list of all VM instances only in the zone us-central1-a with their details.

C An error because the filter syntax is incorrect.

D A list of all VM instances but only their names without details.

💡 Hint

Think about how the filter limits the output to a specific zone.

The filter "zone:(us-central1-a)" restricts the list to instances only in that zone. So the output shows all instances in us-central1-a with their details.

❓ Configuration

intermediate

Which command creates a new persistent disk of 100GB in zone us-east1-b?

You want to create a new persistent disk named 'my-disk' with size 100GB in the zone us-east1-b. Which command will do this correctly?

A gcloud compute disks create my-disk --size=100GB --zone=us-east1-b

B gcloud compute disks create my-disk --zone=us-east1-b --size=100

C gcloud compute disks create --name=my-disk --size=100GB --zone=us-east1-b

D gcloud compute disks create my-disk --size=100GB --region=us-east1-b

💡 Hint

Check the correct order and syntax for the create disk command.

The correct syntax is 'gcloud compute disks create DISK_NAME --size=SIZE --zone=ZONE'. Option A matches this exactly.

❓ Architecture

advanced

What happens if you delete a VM instance with an attached persistent disk without specifying disk deletion?

You delete a VM instance using:

gcloud compute instances delete my-instance --zone=us-west1-c

The instance has a persistent disk attached. What happens to the disk?

A The persistent disk remains and can be attached to other instances later.

B The persistent disk is deleted automatically along with the instance.

C The command fails because you must specify what to do with the disk.

D The persistent disk is detached and becomes read-only.

💡 Hint

Think about default behavior of disks when deleting instances.

By default, deleting an instance does not delete the attached persistent disks. They remain available for reuse.

❓ security

advanced

Which command correctly attaches an existing persistent disk to a running VM instance?

You have a persistent disk named 'data-disk' and a running VM instance 'web-server' in zone us-central1-b. Which command attaches the disk correctly?

A gcloud compute instances attach-disk web-server --disk=data-disk --region=us-central1-b

B gcloud compute disks attach web-server --disk=data-disk --zone=us-central1-b

C gcloud compute instances attach-disk --instance=web-server --disk=data-disk --zone=us-central1-b

D gcloud compute instances attach-disk web-server --disk=data-disk --zone=us-central1-b

💡 Hint

Check the correct command group and flags for attaching disks.

The correct command is 'gcloud compute instances attach-disk INSTANCE_NAME --disk=DISK_NAME --zone=ZONE'. Option D matches this syntax.

✅ Best Practice

expert

What is the best practice to ensure data persistence when deleting VM instances frequently?

You have a workload where VM instances are created and deleted often. You want to keep the data safe and persistent. Which approach is best?

A Use local SSDs attached to the VM instances for fast storage.

B Store data only inside the VM's boot disk and recreate backups manually.

C Use persistent disks and detach them before deleting instances to keep data.

D Use ephemeral disks that delete automatically with the instance.

💡 Hint

Think about which storage survives instance deletion.

Persistent disks remain after instance deletion if detached properly, ensuring data persistence. Local SSDs and ephemeral disks do not persist data after instance deletion.