Autoscaling an Instance Group with Stackdriver Custom Metrics
- Deploy an autoscaling Compute Engine instance group.
- Create a custom metric used to scale the instance group.
- Use the Google Cloud Platform Console to visualize the custom metric and instance group size.
The Node.js script is used to seed a custom metric with values that the instance group can respond to. In a production environment, you would base autoscaling on a metric that is relevant to your use case.
The application includes the following components:
- Compute Engine instance template - A template used to create each instance in the instance group.
- Cloud Storage - A bucket used to host the startup script and other script files.
- Compute Engine startup script - A startup script that installs the necessary code components on each instance. The startup script is installed and started automatically when an instance starts. When the startup script runs, it in turn installs and starts code on the instance that writes values to the Stackdriver custom metric.
- Compute Engine instance group - An instance group that autoscales based on the Stackdriver monitoring metric values.
- Compute Engine instances - A variable number of Compute Engine instances.
- Custom Stackdriver Monitoring metric - A custom monitoring metric used as the input value for Compute Engine instance group autoscaling.
Setup and Requirements
Before you click the Start Lab button
Read these instructions. Labs are timed and you cannot pause them. The timer, which starts when you click Start Lab, shows how long Cloud resources will be made available to you.
This Qwiklabs hands-on lab lets you do the lab activities yourself in a real cloud environment, not in a simulation or demo environment. It does so by giving you new, temporary credentials that you use to sign in and access the Google Cloud Platform for the duration of the lab.
What you need
To complete this lab, you need:
- Access to a standard internet browser (Chrome browser recommended).
- Time to complete the lab.
Note: If you already have your own personal GCP account or project, do not use it for this lab.
How to start your lab and sign in to the Console
Click the Start Lab button. If you need to pay for the lab, a pop-up opens for you to select your payment method. On the left is a panel populated with the temporary credentials that you must use for this lab.
Copy the username, and then click Open Google Console. The lab spins up resources, and then opens another tab that shows the Choose an account page.
Tip: Open the tabs in separate windows, side-by-side.
On the Choose an account page, click Use Another Account.
The Sign in page opens. Paste the username that you copied from the Connection Details panel. Then copy and paste the password.
Important: You must use the credentials from the Connection Details panel. Do not use your Qwiklabs credentials. If you have your own GCP account, do not use it for this lab (avoids incurring charges).
Click through the subsequent pages:
- Accept the terms and conditions.
- Do not add recovery options or two-factor authentication (because this is a temporary account).
- Do not sign up for free trials.
After a few moments, the GCP console opens in this tab.
Activate Google Cloud Shell
Google Cloud Shell is a virtual machine that is loaded with development tools. It offers a persistent 5GB home directory and runs on the Google Cloud. Google Cloud Shell provides command-line access to your GCP resources.
In GCP console, on the top right toolbar, click the Open Cloud Shell button.
In the dialog box that opens, click START CLOUD SHELL:
It takes a few moments to provision and connect to the environment. When you are connected, you are already authenticated, and the project is set to your PROJECT_ID. For example:
gcloud is the command-line tool for Google Cloud Platform. It comes pre-installed on Cloud Shell and supports tab-completion.
You can list the active account name with this command:
gcloud auth list
Credentialed accounts: - <myaccount>@<mydomain>.com (active)
Credentialed accounts: - firstname.lastname@example.org
You can list the project ID with this command:
gcloud config list project
[core] project = <project_ID>
[core] project = qwiklabs-gcp-44776a13dea667a6
Join Qwiklabs to read the rest of this lab...and more!
- Get temporary access to the Google Cloud Console.
- Over 200 labs from beginner to advanced levels.
- Bite-sized so you can learn at your own pace.
Create a GCS bucket
Create an instance template
Create an instance group
Configure autoscaling for the instance group