Terraform on Azure: Production-Ready 3-Tier Architectures

Unlock seamless automation and deployment of production-grade Azure environments with this comprehensive Terraform guide.


Table of contents

  • Prerequisites and Tool Installation


Prerequisites and Tool Installation

1

Azure Account

Ensure you have an active Azure subscription. If not, create a free account.

2

Terraform CLI

Download and install the Terraform CLI from the official HashiCorp website.

3

Azure CLI

Install the Azure CLI to authenticate and manage Azure resources.

4

Text Editor

Choose a suitable text editor or IDE (e.g., VS Code) for writing Terraform code.

Setting Up Azure Credentials and Authentication

Azure CLI Login

Authenticate with Azure using the Azure CLI. Open your terminal and run az login. Follow the prompts to authenticate via your browser.

Service Principal

Create a service principal for Terraform to use. This is a best practice for automation.

Environment Variables

Set the required environment variables, including ARM_CLIENT_ID, ARM_CLIENT_SECRET, ARM_SUBSCRIPTION_ID, and ARM_TENANT_ID.

Organizing Terraform Project Structure

Root Module

Create a root module directory that will contain all Terraform configurations.

Modules Directory

Create a modules directory to store reusable Terraform modules (e.g., network, compute, database).

Environments Directory

Create an environments directory to manage different environments (e.g., dev, staging, prod).

Creating the Root Module Directory

1

Directory Name

Choose a descriptive name for your project (e.g., azure-3tier-prod).

2

Create Directory

Create the directory using the command line: mkdir azure-3tier-prod.

3

Navigate

Navigate into the directory: cd azure-3tier-prod.

Configuring Provider Block for Azure

1

Provider Definition

Create a providers.tf file in the root module directory.

2

Azure Provider

Define the Azure provider with the required authentication details.

Setting Up Remote State Storage in Azure

1
1

Storage Account

Create an Azure Storage Account to store Terraform state files remotely.

2
2

Container

Create a container within the storage account to hold the state file.

3
3

Benefits

Remote state enables collaboration, versioning, and security.

Implementing State Locking Mechanism

1
2
3
1

Prevent Conflicts

State locking prevents concurrent Terraform operations, avoiding state corruption.

2

Azure Storage

Utilize Azure Storage Account's blob locking feature for state locking.

3

Benefits

Enhanced stability and reliability of Terraform deployments.

Defining Backend Configuration

1
2
3
1

Backend Block

Add a backend configuration block to your Terraform code.

2

Storage Details

Specify the Azure Storage Account name, container name, and state file name.

3

Initialization

Run terraform init to initialize the backend.

Creating Resource Groups

Network Architecture Overview

Virtual Network

The core network component.

Subnets

Segment network for each tier.

NSGs

Control traffic flow.

Creating Virtual Network

Configuring Subnet Segmentation

Web Tier Subnet

Dedicated subnet for web servers.

Application Tier Subnet

Subnet for application servers.

Database Tier Subnet

Subnet for database instances with restricted access.

Implementing Network Security Groups

Inbound Rules

Define inbound rules to allow specific traffic (e.g., HTTP/HTTPS to the web tier).

Outbound Rules

Define outbound rules to allow necessary traffic (e.g., web tier to application tier).

Prioritize Rules

Prioritize rules based on security needs and application requirements.

Setting Up Route Tables

1

Default Route

Ensure a default route exists to allow internet access or traffic to other networks.

2

Custom Routes

Create custom routes for specific traffic patterns (e.g., routing traffic through a network virtual appliance).

Configuring Network Peering

Establish Connection

Create peering connections between virtual networks to enable communication.

Configure Access

Configure access control lists (ACLs) to control traffic flow between peered networks.

Use Cases

Ideal for connecting different environments or workloads across virtual networks.

Creating Load Balancers

1

Load Balancer Type

Choose between a public or internal load balancer.

2

Backend Pools

Create backend pools to group VMs for load balancing.

3

Health Probes

Configure health probes to monitor the health of backend VMs.

Setting Up Application Gateway

1

Routing Rules

Define routing rules based on hostnames, paths, and other criteria.

2

SSL Termination

Configure SSL termination for secure communication.

3

Web Tier

Ideal for routing traffic to the web tier based on application-level rules.

Implementing Web Application Firewall

1
1

WAF Policy

Define a Web Application Firewall (WAF) policy to protect against common web exploits.

2
2

Rule Sets

Use pre-configured or custom rule sets to detect and prevent attacks.

3
3

Integration

Integrate WAF with Application Gateway for enhanced security.

Configuring DNS Zones

1
2
3
1

Create Zone

Create an Azure DNS zone for your domain.

2

Records

Add DNS records (A, CNAME, etc.) to point to your application endpoints.

3

Delegation

Delegate your domain to Azure DNS by updating NS records at your domain registrar.

Web Tier Infrastructure Setup

1
2
3
1

Virtual Machines

Create virtual machines or virtual machine scale sets for the web tier.

2

Load Balancer

Configure a load balancer to distribute traffic across web tier instances.

3

Security

Implement network security groups to restrict access to the web tier.

Creating VM Scale Sets for Web Tier

Configuring Web Tier Load Balancing

Load Balancer

Distributes traffic across web server instances.

Health Probes

Monitors the health of web server instances.

Backend Pool

Groups web servers for load balancing.

Implementing Auto-scaling Rules

Setting Up Web Tier Security

Network Security Groups

Control inbound and outbound traffic to the web tier.

Web Application Firewall

Protect against common web exploits.

Regular Security Audits

Ensure compliance with security best practices.

Application Tier Infrastructure

VM Scale Sets

Utilize VM scale sets for scalable application tier instances.

Load Balancer

Configure a load balancer for traffic distribution.

Security

Implement network security groups for enhanced security.

Creating App Tier VM Scale Sets

1

Define Instances

Define the number of instances for the scale set.

2

Configure Scaling

Configure auto-scaling rules based on CPU and memory usage.

3

Placement

Specify the virtual network and subnet for placement.

Configuring App Tier Load Balancing

Internal LB

Use an internal load balancer to distribute traffic.

Pool

Create a backend pool for application servers.

Probe

Configure health probes to monitor server health.

Setting Up Service Discovery

1

Service Registry

Implement a service registry (e.g., Consul, etcd).

2

Register Services

Register application tier services with the registry.

3

Discovery

Use the registry to discover and connect to services.

Implementing App Tier Security

1

NSGs

Use network security groups to control traffic.

2

Microsegmentation

Implement microsegmentation to isolate services.

Database Tier Setup

1
1

Azure SQL

Use Azure SQL Database for managed database services.

2
2

Instances

Create database instances with required configurations.

3
3

Security

Implement robust security measures for database protection.

Creating Azure SQL Instances

1
2
3
1

Deployment

Deploy Azure SQL Database instances in the database subnet.

2

Configure

Configure database settings, including performance tiers and security options.

3

Scaling

Implement scaling rules based on your needs.

Implementing Database Failover Groups

1
2
3
1

Create Group

Create a failover group to enable geographic redundancy.

2

Configure

Configure the failover policy.

3

Add Databases

Add primary and secondary database instances.

Configuring Database Backup

Setting Up Database Security

Encryption

Implement data encryption at rest and in transit.

Firewall

Configure firewall rules to restrict access.

Auditing

Enable auditing to track database activity.

Identity and Access Management

Implementing Role-Based Access Control

Define Roles

Define custom roles with specific permissions.

Assign Roles

Assign roles to users and groups based on their responsibilities.

Least Privilege

Apply the principle of least privilege.

Creating Service Principals

Automation

Use service principals for Terraform automation.

Authentication

Authenticate Terraform with Azure using a service principal.

Security

Grant the service principal the necessary permissions.

Managing Key Vault Integration

1

Create Key Vault

Create an Azure Key Vault to store secrets.

2

Store Secrets

Store database passwords, API keys, and other secrets in Key Vault.

3

Access

Grant Terraform access to Key Vault to retrieve secrets.

Storing Secrets Securely

Don't Hardcode

Avoid hardcoding secrets in Terraform code.

Key Vault

Use Azure Key Vault to store and manage secrets securely.

Access Control

Control access to secrets using RBAC.

Monitoring and Logging Setup

1

Azure Monitor

Utilize Azure Monitor for monitoring and logging.

2

Log Analytics

Set up Log Analytics workspaces.

3

App Insights

Configure Application Insights for application monitoring.

Implementing Azure Monitor

1

Metrics

Collect metrics from Azure resources.

2

Alerts

Create alerts based on metric thresholds.

3

Action Groups

Define action groups to respond to alerts.

Setting Up Log Analytics

1
1

Workspace

Create a Log Analytics workspace.

2
2

Collect Logs

Collect logs from Azure resources.

3
3

Queries

Use Kusto Query Language (KQL) to analyze logs.

Configuring Application Insights

1
2
3
1

Instrumentation

Instrument your application with Application Insights SDK.

2

Metrics

Collect application performance metrics.

3

Analytics

Analyze application performance and identify issues.

Creating Custom Dashboards

1
2
3
1

Choose Metrics

Select relevant metrics to display.

2

Layout

Design the dashboard layout.

3

Share

Share the dashboard with stakeholders.

Disaster Recovery Configuration

Implementing Backup Solutions

Regular Backups

Schedule regular backups.

Replication

Implement data replication.

Setting Up Geographic Redundancy

Creating Recovery Services Vault

Create Vault

Create a Recovery Services vault.

Configure

Configure backup policies and settings.

Protect Resources

Protect Azure resources by associating them with the vault.

Defining Backup Policies

Frequency

Define backup frequency.

Retention

Set retention period.

Schedule

Schedule backup jobs.

Security Implementation

1

Azure Security Center

Utilize Azure Security Center for security assessments.

2

DDoS Protection

Implement DDoS protection.

3

Azure Firewall

Use Azure Firewall to protect your network.

Configuring Azure Security Center

Assessments

Review security assessments.

Recommendations

Implement security recommendations.

Alerts

Monitor security alerts.

Implementing DDoS Protection

1

Enable Protection

Enable DDoS Protection Standard.

2

Configure

Configure DDoS protection settings.

Setting Up Azure Firewall

1

Deploy Firewall

Deploy Azure Firewall in your virtual network.

2

Configure Rules

Configure network and application rules.

Network Security Best Practices

1
1

Segmentation

Segment your network using subnets and NSGs.

2
2

Least Privilege

Apply the principle of least privilege.

Performance Optimization

1
2
3
1

Caching

Implement caching solutions.

2

CDN

Use a content delivery network (CDN).

3

Traffic Manager

Configure Traffic Manager for global load balancing.

Implementing Caching Solutions

1
2
3
1

Azure Cache

Use Azure Cache for Redis.

2

Configure Cache

Configure caching policies.

3

Application Integration

Integrate with your application.

Configuring CDN

Setting Up Traffic Manager

Traffic Manager

Configure Traffic Manager for global load balancing.

Performance Testing Setup