Why Netflix Uses Terraform: A Case Study in Scalable Infrastructure Management

Introduction

Netflix, the world's leading streaming service, serves millions of customers daily. To maintain the high availability, scalability, and performance of its platform, Netflix relies heavily on cloud infrastructure. Given the scale of its operations, manual management of infrastructure is impractical. This is where Terraform comes into play. In this case study, we will explore why Netflix uses Terraform to manage its cloud infrastructure and how it contributes to the platform's seamless scalability and resilience.

Background

Netflix’s infrastructure is based on microservices architecture, primarily running on Amazon Web Services (AWS). With hundreds of microservices and thousands of EC2 instances, Netflix’s infrastructure is dynamic, requiring constant provisioning, configuration, and management of resources.

As Netflix's user base grew globally, it needed a solution to manage its multi-region, multi-cloud environments efficiently. Netflix adopted Terraform—a popular Infrastructure as Code (IaC) tool developed by HashiCorp—to address these challenges.

Challenges Faced by Netflix

1. Infrastructure Scalability

Netflix's infrastructure must be capable of scaling quickly to meet increasing traffic demands, especially during popular show releases. Provisioning new instances and configuring infrastructure manually was inefficient and prone to errors.

2. Multi-Region Deployment

Netflix operates in numerous regions globally, so it required an infrastructure solution that could easily manage multi-region deployments. AWS offers regional services, and Netflix needed a way to manage resources consistently across these regions.

3. Cross-Cloud Compatibility

While Netflix predominantly runs on AWS, it needed to maintain the ability to be cloud-agnostic. Ensuring that their infrastructure could be migrated or replicated across different cloud platforms required a cross-cloud infrastructure management tool.

4. Automation and Consistency

Manual configurations often resulted in inconsistencies between environments, leading to potential outages and performance degradation. Netflix needed a standardized, automated approach to manage its infrastructure that ensured reliability across its environments.

Why Netflix Chose Terraform

1. Infrastructure as Code (IaC)

Terraform enables Netflix to define its entire cloud infrastructure using code. By using HCL (HashiCorp Configuration Language), Netflix can define and provision resources such as EC2 instances, load balancers, and VPCs as code. This makes infrastructure easily replicable and version-controlled.

2. Multi-Cloud Support

Terraform’s ability to support multiple cloud platforms (AWS, Google Cloud, Azure) is one of its key features. Although Netflix primarily uses AWS, Terraform allows the flexibility to shift or extend their workloads to other cloud platforms if necessary, without needing to adopt a new IaC tool.

3. Automation and Consistency

With Terraform, Netflix can automate the provisioning, scaling, and decommissioning of resources, ensuring that the infrastructure remains consistent across all environments. This automation eliminates human error, reduces downtime, and enables rapid iteration in development and deployment processes.

4. Modular and Reusable Code

Terraform supports modularity, meaning Netflix can create reusable modules for frequently used resources such as EC2 instances, security groups, and auto-scaling groups. This allows different teams at Netflix to use pre-built, validated templates for setting up infrastructure quickly and reliably.

5. State Management

Terraform maintains the state of infrastructure, meaning it tracks resource changes over time. Netflix can use Terraform’s state files to understand what infrastructure currently exists and make updates without affecting unrelated resources. This is crucial for managing complex microservices architectures and thousands of resources across multiple regions.

6. Collaboration and Version Control

Terraform integrates with version control systems like Git, allowing Netflix’s teams to collaborate on infrastructure code. By versioning infrastructure configurations, Netflix can track changes, roll back to previous versions if necessary, and ensure that only tested configurations are deployed in production.

How Netflix Uses Terraform

1. Scaling Infrastructure

During major content releases, such as the launch of popular shows or movies, Netflix experiences significant spikes in traffic. Terraform automates the provisioning of additional cloud resources (like EC2 instances and databases) to handle this surge in real-time. This ensures smooth playback for users, even during peak load times.

2. Multi-Region Redundancy

Netflix leverages Terraform to automate deployments across multiple AWS regions to ensure high availability and low latency for its global user base. With Terraform, Netflix can replicate its infrastructure in multiple regions quickly, improving fault tolerance and disaster recovery capabilities.

3. Microservices Management

Netflix’s microservices architecture, with hundreds of independent services, requires careful resource management. Terraform modules allow Netflix teams to define and deploy microservices in a standardized way, reducing complexity and improving deployment speed.

4. Automated Infrastructure Testing

Terraform integrates with Netflix's continuous integration/continuous deployment (CI/CD) pipelines, allowing for automated infrastructure testing. Netflix runs tests on infrastructure changes before applying them in production, ensuring that updates do not negatively impact the platform's performance.

Benefits Netflix Gains from Terraform

1. Faster Time-to-Market

Terraform enables Netflix to provision infrastructure quickly, allowing teams to launch new features and services faster. This agility is critical in staying ahead in the competitive streaming industry.

2. Reduced Operational Costs

By automating infrastructure management, Netflix reduces the need for manual intervention, lowering operational costs and reducing the risk of downtime caused by human errors.

3. High Availability and Resilience

Terraform’s ability to automate multi-region deployments and manage failover scenarios ensures that Netflix's platform is highly available and resilient, even in the face of regional outages.

4. Cross-Cloud Flexibility

Netflix is not locked into a single cloud provider. Terraform’s multi-cloud capabilities give Netflix the flexibility to expand or migrate its workloads across different cloud platforms if needed.

5. Improved Collaboration

Terraform’s integration with version control systems like Git allows for better collaboration across Netflix’s engineering teams. Teams can work together on infrastructure code, track changes, and ensure only validated configurations reach production.

Conclusion

Terraform plays a pivotal role in Netflix’s infrastructure management strategy by enabling rapid scaling, ensuring consistency across environments, and improving collaboration. By automating infrastructure tasks, Netflix ensures high availability, scalability, and resilience while also maintaining operational efficiency. For a platform as large as Netflix, Terraform provides the flexibility and power needed to manage its global cloud infrastructure with confidence.

Key Takeaways

• Terraform helps Netflix automate infrastructure provisioning, reduce human error, and scale efficiently.

• Its multi-cloud support allows Netflix to remain flexible and future-proof.

• By using Terraform’s IaC approach, Netflix can manage its massive infrastructure consistently and efficiently.