Terraform – Create OCI VCN & Internet Gateway (Step-by-Step Guide)

This lab demonstrates how to create a Virtual Cloud Network (VCN) in Oracle Cloud Infrastructure (OCI) using Terraform and attach an Internet Gateway for public access.

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1. Get the VCN Creation Template

Go to Terraform Provider OCI Docs
and search for oci_core_vcn to get the VCN creation template.

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2. Navigate to Code Editor

Open your preferred code editor to create the Terraform files.

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3. Write Terraform Code to Create a VCN

a. main.tf

provider "oci" {
  region = "us-ashburn-1" // Replace with your desired region
}

resource "oci_core_vcn" "example_vcn" {
  cidr_block     = "10.0.0.0/16"
  display_name   = "example-vcn"
  compartment_id = "ocid1.compartment.oc1..exampleuniqueID" // Replace with your compartment OCID
  dns_label      = "examplevcn"
}

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b. variables.tf (Optional)

variable "compartment_id" {
  description = "The OCID of the compartment where the VCN will be created"
  type        = string
}

variable "region" {
  description = "The OCI region"
  type        = string
  default     = "us-ashburn-1"
}

variable "vcn_cidr" {
  description = "The CIDR block for the VCN"
  type        = string
  default     = "10.0.0.0/16"
}

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c. outputs.tf

output "vcn_id" {
  value = oci_core_vcn.example_vcn.id
}

output "vcn_cidr_block" {
  value = oci_core_vcn.example_vcn.cidr_block
}

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4. Initialize Terraform

Run the following commands from your project directory:

a. Initialize Terraform

terraform init

b. Validate the Configuration

terraform validate

c. Preview the Changes

terraform plan -var="compartment_id=<your_compartment_ocid>"

d. Apply the Configuration

terraform apply -var="compartment_id=<your_compartment_ocid>"

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5. Verify the VCN

• Check the Terraform output for VCN ID and CIDR block.
• Log in to OCI Console → Networking → Virtual Cloud Networks to confirm the VCN creation.

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6. Clean Up (Optional)

To remove the VCN and associated resources:

terraform destroy -var="compartment_id=<your_compartment_ocid>"

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✅ Suggested Wiki Page Title:
Terraform – Create OCI VCN & Internet Gateway (Illustrated Guide)