Terraform KVM Infrastructure

This project uses Terraform and KVM (Kernel-based Virtual Machine) to create various infrastructure scenarios. You simply need to provide the necessary values in the terraform.tfvars file and then run Terraform to set up your virtual machines.

Prerequisites

Before starting, ensure that the following are installed on your system:

• Terraform: for infrastructure management as code.
• KVM: for creating and managing virtual machines.
• libvirt: for interacting with KVM.

Installing Prerequisites on Ubuntu

1. Install Terraform

To install Terraform on Ubuntu, first download the appropriate version for your system:

1. Update and install dependencies:

   sudo apt-get update && sudo apt-get install -y wget unzip

2. Download and install Terraform:

   wget https://releases.hashicorp.com/terraform/$(curl -s https://checkpoint-api.hashicorp.com/v1/check/terraform | jq -r .current_version)/terraform_$(curl -s https://checkpoint-api.hashicorp.com/v1/check/terraform | jq -r .current_version)_linux_amd64.zip
   unzip terraform_*.zip
   sudo mv terraform /usr/local/bin/
   terraform -v

   These commands will automatically download and install the latest version of Terraform.

2. Install KVM and libvirt

To install KVM and libvirt on Ubuntu-based systems, run the following commands:

1. Update and install dependencies:

   sudo apt update
   sudo apt install -y qemu-kvm libvirt-bin bridge-utils virt-manager

2. Ensure that the libvirt service is running:

   sudo systemctl enable libvirtd
   sudo systemctl start libvirtd

3. Make sure your user is added to the libvirt group:

   sudo usermod -aG libvirt $(whoami)

4. To verify that KVM is installed successfully, run:

   kvm-ok

   If the result is "KVM acceleration can be used," the installation was successful.

Setting Up the Project

1. Cloning the Project and Navigating to the KVM Directory

To get started, clone the project from GitHub and navigate to the project directory.

1.1. Clone the Project from GitHub

To clone the project, use the following command:

git clone https://github.com/nazari-mohsen/terraform.git

(Replace username with the actual username of the repository owner.)

1.2. Navigate to the Project Directory

After cloning, go into the project directory:

cd kvm

Steps to Configure the terraform.tfvars File:

1. Copy the file terraform.tfvars.sample from the sample directory.
2. Paste it in the kvm directory and rename it as terraform.tfvars.
3. Update the values in the terraform.tfvars file to reflect your own configuration (such as paths, SSH keys, VM specifications, etc.).

Default OS Image:

By default, the OS image used is the noble-server-cloudimg-arm64.img image from:

Ubuntu Cloud Images

You can download this image and place it in your desired directory. After downloading, update the source_path variable in the terraform.tfvars file to point to the location where you saved the image.

2. Configure the terraform.tfvars File

Once you're in the project directory, create the terraform.tfvars file and enter the necessary values to configure your virtual machines.

Sample terraform.tfvars File:

# Path to the cloud-init file for virtual machine configuration
cloud_init_file = "./cloudinit/cloud_init.cfg"

# Type and path for KVM storage configuration
pool_type       = "dir"
libvirt_url     = "qemu:///system"
pool_path       = "/home/user/Volume/kvm"

# Path to the OS image for virtual machines
source_path     = "/home/user/Downloads/noble-server-cloudimg-amd64.img"

# SSH key for accessing the virtual machines
ssh_key         = "ssh_key"

# Virtual Machine definitions
vm_definitions = [
  # Method 1: Define master, worker, loadbalancer VMs
  { type = "master", count = 3, memory = 2048, vcpu = 2, size_disk = 10361393152 },
  { type = "worker", count = 2, memory = 4048, vcpu = 4, size_disk = 10361393152 },
  { type = "loadbalancer", count = 1, memory = 1024, vcpu = 1, size_disk = 10361393152 }
]

# Method 2: Use an alternative definition for virtual machines
vm_definitions_alt = [
  { type = "vm", count = 3, memory = 2048, vcpu = 2, size_disk = 10361393152 }
]

3. Running Terraform

Once the values are configured in the terraform.tfvars file, follow these steps to run Terraform:

3.1. Initialize Terraform

First, initialize Terraform:

terraform init

3.2. Review the Infrastructure Plan

To check if everything is configured correctly, run the following command to review the infrastructure plan:

terraform plan

3.3. Apply the Changes

After confirming the plan, run the following command to create the virtual machines and infrastructure:

terraform apply

This will automatically create the virtual machines based on the configuration in the terraform.tfvars file.

4. Accessing the Virtual Machines

After the virtual machines are created, you can access them via SSH. Use the SSH key defined in the terraform.tfvars file to connect to the virtual machines.

ssh -i path_to_your_ssh_key user@vm_ip

5. Destroying Infrastructure

If you wish to remove the created infrastructure, use the following command:

terraform destroy

This will delete all the virtual machines and resources managed by Terraform.

Additional Notes

• cloud-init: The cloud_init.cfg file is used for initial virtual machine configuration (e.g., networking, users, and other OS-level settings). You can modify this file as per your requirements.

• Disk Size and Resources: You can adjust the memory, vcpu, and size_disk values based on your needs. The disk size and resources (CPU/RAM) should be chosen according to the type of virtual machine and the workload it will handle.

• Number of Machines: For each machine type (master, worker, loadbalancer), you can specify the desired number of machines. In the example above, we define 3 master machines, 2 worker machines, and 1 loadbalancer.

Support

For support or to report issues, please open a new Issue on GitHub Issues.

License

This project is licensed under the Apache-2.0 license.