# How to create an instance with Terraform?

Learn how to launch an instance using Terraform with this step-by-step tutorial. 

### **What is a Terraform?**

Terraform is an infrastructure provisioning tool that allows you to construct infrastructure using code, often called Infrastructure as Code. Terraform, as a result, enables you to automate and maintain your infrastructure, platform, and applications that operate on that platform.

### **How does Terraform function?**

Terraform uses configuration files and version control to define and manage your whole infrastructure. This is accomplished by utilizing the two primary components of Terraform architecture: Core and Providers.

Read and follow these instructions carefully. The instructions below describe how to create an instance with Terraform on Ubuntu.

### Get Sarted

#### **Step 1: Install Terraform**

(a) Add the HashiCorp GPG key.

```
curl -fsSL https://apt.releases.hashicorp.com/gpg | sudo apt-key add -
```

(b) For Terraform Repository.

```
sudo apt-add-repository "deb [arch=amd64] https://apt.releases.hashicorp.com $(lsb_release -cs) main"
```

(c) Run the system update command and install Terraform.

```
sudo apt-get update && sudo apt-get install terraform
```

(d) Check if Terraform is installed correctly or not.

```
terraform -v
```

#### **Step 2: Creating a provider**

You specify "providers" for your cloud environment in Terraform. Your OpenStack infrastructure resources are hosted by a "provider."\
Make a file called provider.tf.

```
touch providers.tf
nano providers.tf
```

#### **Step 3: Paste the following code**

The OpenStack provider is used to communicate with the numerous OpenStack resources. Before it can be utilized, the provider must be set up with the appropriate credentials.

```
terraform {
  required_providers {
    openstack = {
      source  = "terraform-provider-openstack/openstack"
      version = "~> 1.48.0"
    }
  }
}

provider "openstack" {
  user_name   = var.username
  tenant_name = var.project_name
  password    = var.password
  auth_url    = "https://api-us-east-at-1.openstack.acecloudhosting.com:5000"
  region      = "us-east-at-1"
}
```

#### **Step 4: Initialize the Terraform environment**

Now, you need to initialize the working directory, which actually contains the terraform .tf file.

```
terraform init
```

#### **Step 5: Create a variable file**

```
touch variables.tf
nano varibles.tf
```

#### **Step 6: Paste the following variables and edit as per your usage**

```
variable "username" {

 type = string

 description = "Please enter your username for cloud console"

}

variable "password" {

 type = string

 description = "Please enter password for your cloud console"

}

variable "project_name" {

 type = string

 description = "Please mention the name of your project"

}


variable "instance_name" {

 type = string

 description = "Name of the instance to be created"

 default = "myinstance"

}

variable "region_name" {

 type = string

 description = "Name of the region where instance is to be created"

 default = "us-east-at-1"

 sensitive = true

}

variable "count_instance" {

 description = "Number of instances to be created"

 default = 1

}

variable "image_id" {

type = string

description = "ID of the image to be used with instance"

default = "c83dd18c-a2fa-4a85-91fb-553e16397be1"

}

variable "flavor_name" {

 type = string

 description = "Name of the flavor to be used with the instance"

 default = "c.8"

 sensitive = true

}

variable "key_name" {

 type = string

 description = "Name of the key to be associated with the instance"

 default = "mykeypair"

}

variable "volume_size" {

 description = "Size of the volume to be used with the instance"

 default = 10

}
```

#### **Step 7: Create the main file**

```
touch main.tf
nano main.tf
```

#### **Step 8: Paste the following command**

```
#Creating an instance
resource "openstack_compute_instance_v2" "instance_1" { #Resource block to create an instance with a volume
  name            = var.instance_name
  region          = var.region_name
  count           = var.count_instance
  flavor_name       = var.flavor_name
  key_pair        = var.key_name
  network {
    name      = "External_Net" # name of the network to be used
  }
  security_groups = ["default"] #Security group name from the cloud



 block_device {
    uuid                  = var.image_id
    source_type           = "image"
    destination_type      = "volume"
    volume_size           = var.volume_size
    boot_index            = 0
    delete_on_termination = true #set to false to save volume for backup
  }
}
```

#### **Step 9: Create an execution plan**

This command is a quick method to see if the execution plan for a set of modifications fits your expectations without affecting actual resources or the state.

*After executing the command, enter your console username, password, and project name.*

```
terraform plan
```

#### **Step 10: Execute the actions**

```
terraform apply
```

*After executing the command, enter your console username, password, and project name again and enter yes to confirm.*

Now instance has been created, you can verify it on the portal.

#### **Step 11: Delete the instance**

```
terraform destroy
```

After executing the command, enter yes to confirm. Your instance will be deleted.