Sunday, 7 September 2025

Mastering Terraform Providers & Multiple Resources: Build Infrastructure Smarter and Faster (Part 4)

Standard

So far, we’ve built a single resource in Terraform using variables and outputs.

But in real-world projects, you’ll need:

  • Multiple resources (e.g., S3 buckets, EC2 instances, databases)
  • Integration with different providers (AWS, Azure, GCP, Kubernetes, etc.)

In this blog, we’ll cover:

  • What Providers are in Terraform
  • Creating multiple resources efficiently
  • Real-world use cases and best practices

What are Providers in Terraform?

Think of providers as plugins that let Terraform talk to different services.

  • AWS Provider → Manages AWS services like S3, EC2, RDS.
  • Azure Provider → Manages Azure resources like VMs, Storage, Databases.
  • GCP Provider → Manages Google Cloud resources like Buckets, VMs, BigQuery.

When you run terraform init, it downloads the required provider plugins.

Example: AWS Provider Setup

provider "aws" {
  region = var.region
}

Here:

  • provider "aws" → Tells Terraform we’re using AWS
  • region → Where resources will be deployed

Creating Multiple Resources

Let’s say we want 3 S3 buckets.
Instead of writing 3 separate resource blocks, we can use the count argument.

resource "aws_s3_bucket" "my_buckets" {
  count  = 3
  bucket = "my-terraform-bucket-${count.index}"
  acl    = "private"
}

This will create:

  • my-terraform-bucket-0
  • my-terraform-bucket-1
  • my-terraform-bucket-2

Using for_each for Named Buckets

If you want custom names:

variable "bucket_names" {
  default = ["dev-bucket", "staging-bucket", "prod-bucket"]
}

resource "aws_s3_bucket" "my_buckets" {
  for_each = toset(var.bucket_names)
  bucket   = each.key
  acl      = "private"
}

Now each bucket gets a name from the list.

Real-World Case Study: Multi-Environment Infrastructure

A startup managing dev, staging, and prod environments:

  • Used for_each to create resources for each environment automatically.
  • Added environment-specific tags for easy cost tracking in AWS.
  • Used one Terraform script for all environments instead of maintaining 3.

Result: Reduced code duplication by 70%, simplified deployments.

Multiple Providers in One Project

Sometimes you need resources across multiple clouds or services.

Example: AWS for compute + Cloudflare for DNS.

provider "aws" {
  region = "us-east-1"
}

provider "cloudflare" {
  api_token = var.cloudflare_api_token
}

Now you can create AWS S3 buckets and Cloudflare DNS records in one Terraform project.

Best Practices

  1. Separate provider configurations for clarity when using multiple providers.
  2. Use variables for region, environment, and sensitive data.
  3. Tag all resources with environment and owner info for cost tracking.
  4. Use workspaces for managing dev/staging/prod environments cleanly.

What’s Next?

Now we know:

  • How providers connect Terraform to services
  • How to create multiple resources with minimal code

Bibliography