Provisioning a Compute Engine on Google Cloud Platform (GCP) using Terraform

Introduction

Welcome to the comprehensive guide for setting up infrastructure on Google Cloud Platform (GCP) and establishing a connection to Visual Studio Code (VS Code) using Terraform.

Prerequisite

1. Install Terraform

   Install Terraform on your local machine. You can download the appropriate Terraform package for your operating system from the official Terraform website and follow the installation instructions for your platform. Ensure that Terraform is added to your system's PATH to enable running Terraform commands from the terminal or command prompt.

   To verify the installation, open a terminal or command prompt and type

   terraform -v
   

   This command should display the installed Terraform version.

2. Create Service Account

   1. Access your GCP Console using your credentials.
   2. Navigate to the IAM & Admin section in the GCP Console.
   3. Select Service Accounts and click on Create Service Account
   4. Fill in the necessary details for the service account, such as name and description.
   5. Assign the role Compute Admin to the service account. This role grants the necessary permissions to manage Compute Engine resources.
   6. After creating the service account, generate and download the key for this service account as a JSON file.
   7. This key file contains the authentication credentials required by Terraform to manage resources on GCP.
   8. Save Key Contents to tfkey.json:
   9. Once the JSON key file is downloaded, open the file and copy its contents.
   10. Create a file named tfkey.json in the directory where you'll be working with your Terraform code.
   11. Paste the contents of the downloaded JSON key into the tfkey.json file.
   Warning

   Ensure the key file (tfkey.json) remains secure and isn't shared publicly, as it contains sensitive authentication information allowing access to your GCP resources.

3. SSH Key Generation

   1. Use the following command to generate an SSH key pair:

      ssh-keygen -t rsa -f ce -C ubuntu -b 2048
      

      • -t rsa: Specifies the type of key to create (RSA).
      • -f ce: Sets the file name of the generated key to 'ce' (You can change 'ce' to a name of your choice).
      • -C ubuntu: Provides a comment, typically the username or a descriptive tag.
      • -b 2048: Specifies the number of bits in the key (2048-bit key in this case).
   2. Upon execution, you might be prompted to enter a passphrase to secure your private key. Press Enter for an empty passphrase if you prefer not to use one.
   3. The command will generate two files: ce (private key) and ce.pub (public key) in your current directory.
   4. The corresponding public key (ce.pub) can be shared with your Compute Engine instance or other services for authentication.
   Warning

   Ensure the private key (ce) remains secure and isn't shared publicly. This private key will be used to authenticate SSH connections to your Compute Engine instance.

Tutorials

1. Update the .tfvars (Terraform variables) file.

   project_id = "emerald-road-403117"
   region = "us-east1"
   zone = "us-east1-b"
   name = "class-demo-redis"
   ssh_key_filename = "ce-tf"
   machine_type = "e2-standard-4"
   storage = 100
   

   1. project_id: Replace the value with your specific GCP Project ID.
   2. region: Set the desired region for deploying resources in GCP.
   3. zone: Choose the appropriate zone within the specified region.
   4. name: Define a unique name for the Compute Engine instance or resource.
   5. ssh_key_filename: Enter the name of the SSH key file generated previously.
   6. machine_type: Select the desired machine type for the Compute Engine instance.
   7. storage: Specify the amount of storage required for the instance (in GB).

2. Update the main.tf file to open the firewall ports

   allow {
       protocol = "tcp"
       ports    = ["80", "8080", "50001", "50002", "50003", "50004"] # TODO: Change ports as required
   }
   

3. Initialize the Terraform Configuration

   Execute the following command in your terminal or command prompt to initialize your Terraform configuration:

   terraform init
   

   This command initializes the working directory and prepares the configuration, ensuring all necessary plugins and modules are downloaded.

4. Generate and Review an Execution Plan:

   To view the changes Terraform will apply before actually deploying the infrastructure, use the following command:

   terraform plan
   

   This command generates an execution plan by examining the current state of your infrastructure and comparing it to the desired state defined in your configuration files (*.tf). Review the proposed changes in the plan output.

   Sample output:

   Plan: 3 to add, 0 to change, 0 to destroy.
   
   Changes to Outputs:
   + ExternalIP = (known after apply)
   

5. Apply Changes to Deploy Infrastructure Execute the following command to apply the changes defined in your Terraform configuration and deploy the infrastructure:

   terraform apply
   

   The apply command implements the changes defined in your configuration files, creating or modifying the infrastructure according to the execution plan. It prompts for confirmation before making any changes.

   Sample output:

   Apply complete! Resources: 3 added, 0 changed, 0 destroyed.
   
   Outputs:
   ExternalIP = "34.139.43.201"
   

6. SSH Connection using the Generated Key Use the following command in your terminal to connect to your Compute Engine instance via SSH:

   ssh -i ce ubuntu@34.139.43.201
   

   1. -i ce: Specifies the identity file (private key) for authentication. Replace ce with the actual name of your SSH private key file. 2. ubuntu@34.139.43.201: Replace this with the actual username and IP address (or hostname) of your Compute Engine instance.

7. Deploying Services and Docker Containers to Compute Engine

   To run your application services on your Compute Engine instance, follow these steps:

   1. Clone Repository and Prepare Environment
   2. Build Docker Image
   3. Run Docker Compose

   This will facilitate running your application services within containers on the remote server.

8. Destroy Resources

   Warning

   Proceed once you no longer require the resources

   If you intend to remove all resources defined in your configuration, you can execute the following command:

   terraform destroy
   

   The destroy command removes all resources defined in your Terraform configuration. It is irreversible and should be used judiciously, as it will delete the provisioned infrastructure. Sample output:

   Destroy complete! Resources: 3 destroyed.
   

Continued exploration and further customization of the deployed resources can enhance and optimize the infrastructure, catering to specific project requirements and evolving needs.

Happy provisioning and managing your infrastructure on GCP with Terraform!