Google Compute Engine Project Metadata

This page shows how to write Terraform for Compute Engine Project Metadata and write them securely.

google_compute_project_metadata (Terraform)

The Project Metadata in Compute Engine can be configured in Terraform with the resource name google_compute_project_metadata. The following sections describe 3 examples of how to use the resource and its parameters.

Example Usage from GitHub

metadata.tf#L1
resource "google_compute_project_metadata" "frontend" {
  project = module.project_frontend.project_id
  metadata = {
    enable-guest-attributes: "TRUE"
    enable-oslogin: "TRUE"
    enable-osconfig: "TRUE"
positive.tf#L1
resource "google_compute_project_metadata" "positive1" {
  metadata = {
    enable-oslogin = false
  }
}

positive.tf#L1
resource "google_compute_project_metadata" "positive1" {
  metadata = {
    enable-oslogin = false
  }
}

Review your Terraform file for Google best practices

Shisho Cloud, our free checker to make sure your Terraform configuration follows best practices, is available (beta).

Security Best Practices for google_compute_project_metadata

There is 1 setting in google_compute_project_metadata that should be taken care of for security reasons. The following section explain an overview and example code.

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Ensure OS login for your GCE instances is enabled at project level

It is better to enable OS login for your GCE instances. Enabling OS login ensures that SSH keys used to connect to instances are mapped with IAM users, allowing centralized and automated SSH key management.

Review your Google Compute Engine settings

You can check if the google_compute_project_metadata setting in your .tf file is correct in 3 min with Shisho Cloud.

Parameters

  • id optional computed - string
  • metadata required - map from string to string

A series of key value pairs.

The ID of the project in which the resource belongs. If it is not provided, the provider project is used.

Explanation in Terraform Registry

Authoritatively manages metadata common to all instances for a project in GCE. For more information see the official documentation and API.

Note: This resource manages all project-level metadata including project-level ssh keys. Keys unset in config but set on the server will be removed. If you want to manage only single key/value pairs within the project metadata rather than the entire set, then use google_compute_project_metadata_item.

Tips: Best Practices for The Other Google Compute Engine Resources

In addition to the google_compute_disk, Google Compute Engine has the other resources that should be configured for security reasons. Please check some examples of those resources and precautions.

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google_compute_disk

Ensure the encryption key for your GCE disk is stored securely

It is better to store the encryption key for your GCE disk securely. Secret Manager could be used instead.

risk-label

google_compute_firewall

Ensure your VPC firewall blocks unwanted outbound traffic

It is better to block unwanted outbound traffic not to expose resources in the VPC to unwanted attacks.

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google_compute_instance

Ensure appropriate service account is assigned to your GCE instance

It is better to create a custom service account for the instance and assign it.

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google_compute_ssl_policy

Ensure to use modern TLS protocols

It's better to adopt TLS v1.2+ instead of outdated TLS protocols.

risk-label

google_compute_subnetwork

Ensure VPC flow logging is enabled

It is better to enable VPC flow logging. VPC flow logging allows us to audit traffic in your network.

Review your Google Compute Engine settings

In addition to the above, there are other security points you should be aware of making sure that your .tf files are protected in Shisho Cloud.

Frequently asked questions

What is Google Compute Engine Project Metadata?

Google Compute Engine Project Metadata is a resource for Compute Engine of Google Cloud Platform. Settings can be wrote in Terraform.

Where can I find the example code for the Google Compute Engine Project Metadata?

For Terraform, the stliang/ferrops, Checkmarx/kics and leonidweinbergcx/mykics source code examples are useful. See the Terraform Example section for further details.