Managed instance groups in GCP - Mini Project: Build & Apply

Create a Managed Instance Group on Google Cloud

📖 Scenario: You are setting up a scalable web application on Google Cloud. To handle traffic efficiently, you want to create a group of virtual machines that can automatically grow or shrink based on demand.

🎯 Goal: Build a Managed Instance Group (MIG) using Google Cloud CLI commands that launches multiple instances from a template and can scale automatically.

📋 What You'll Learn

Create an instance template named web-template with a Debian image

Create a managed instance group named web-mig in the us-central1-a zone using the web-template

Set the initial size of the managed instance group to 2 instances

Configure autoscaling for the managed instance group to scale between 2 and 5 instances based on CPU utilization at 60%

💡 Why This Matters

🌍 Real World

Managed instance groups help run applications that need to handle changing traffic by automatically adding or removing virtual machines.

💼 Career

Cloud engineers and DevOps professionals use managed instance groups to ensure applications are scalable, reliable, and cost-efficient.

1

Create an instance template

Use the gcloud command to create an instance template named web-template with the Debian 11 image.

GCP

# Use gcloud to create an instance template named web-template with Debian 11
# Your code here

Need a hint?

Use gcloud compute instance-templates create with --image-family=debian-11 and --image-project=debian-cloud.

2

Create a managed instance group

Create a managed instance group named web-mig in the us-central1-a zone using the instance template web-template and set the size to 2.

GCP

gcloud compute instance-templates create web-template --machine-type=e2-small --image-family=debian-11 --image-project=debian-cloud
# Create a managed instance group named web-mig in us-central1-a with size 2 using web-template
# Your code here

Need a hint?

Use gcloud compute instance-groups managed create with --size 2, --template web-template, and --zone us-central1-a.

3

Configure autoscaling for the managed instance group

Set autoscaling on the managed instance group web-mig in us-central1-a to scale between 2 and 5 instances based on CPU utilization at 60%.

GCP

gcloud compute instance-templates create web-template --machine-type=e2-small --image-family=debian-11 --image-project=debian-cloud
gcloud compute instance-groups managed create web-mig --base-instance-name web-instance --size 2 --template web-template --zone us-central1-a
# Configure autoscaling for web-mig to scale between 2 and 5 instances at 60% CPU utilization
# Your code here

Need a hint?

Use gcloud compute instance-groups managed set-autoscaling with the correct flags for min, max replicas and CPU utilization.

4

Verify the managed instance group configuration

Add the command to describe the managed instance group web-mig in us-central1-a to check its configuration.

GCP

gcloud compute instance-templates create web-template --machine-type=e2-small --image-family=debian-11 --image-project=debian-cloud
gcloud compute instance-groups managed create web-mig --base-instance-name web-instance --size 2 --template web-template --zone us-central1-a
gcloud compute instance-groups managed set-autoscaling web-mig --max-num-replicas 5 --min-num-replicas 2 --target-cpu-utilization 0.6 --zone us-central1-a
# Describe the managed instance group web-mig in us-central1-a to verify configuration
# Your code here

Need a hint?

Use gcloud compute instance-groups managed describe with the group name and zone.