In the world of cloud, hybrid, and on-premises Infrastructure as Code (IaC), where managing and provisioning infrastructure through code has become indispensable, tools like OpenTofu play a pivotal role. The evolutions of IaC tools continues with OpenTofu, as a fork of Terraform that offers a more open-source, community-driven alternative that is managed by the Linux Foundation. In this article, we’ll look at what OpenTofu is, why it was created, what its purpose is, and take a basic look at migrating to OpenTofu from Terraform.

What is OpenTofu?

OpenTofu is an infrastructure as code tool that enables users to define infrastructure resources in human-readable configuration files. These files can be versioned, reused, and shared, providing a consistent workflow for provisioning and managing infrastructure throughout its lifecycle. While based on Terraform, OpenTofu distinguishes itself with its open-source nature and community-driven development.

The main goals of OpenTofu are:

• Truly open source – under a well-known and widely-accepted license that companies can trust, that wont suddenly change in the future, and isn’t subject to the whims of a single vendor
• Community driven – the community governs the project for the community, where pull requests are regularly reviewed and accepted on their merit
• Impartial – so that valuable features and fixes are accepted based on their value to the community; regardless of their impact on any particular vendor
• Layered and modular – programmer-friendly project structure to encourage building on top, enabling a new vibrant ecosystem of tools and integrations
• Backwards compatible – existing code can drive value for years to come

Why was OpenTofu Created?

OpenTofu emerges from a confluence of factors driving innovation and evolution in the infrastructure management landscape. Its creation is rooted in addressing key challenges and advancing the principles of openness, collaboration, and adaptability.

HashiCorp originally open sourced Terraform back in 2014 under the Mozilla Public License v2.0 (MPL). The entire Terraform ecosystem and community built up to be one of the most used IaC tools in the industry with a huge ecosystem of open-source modules, plugins, libraries, and extensions. Then, on August 10th, 2023, HashiCorp decided to switch the license of Terraform from the MPL to the Business Source License (v1.1) (BUSL); a non-open source license that is more of a “source available” license. HashiCorp did this with little advanced notice or much a chance for the community to offer any input on the decision.

In response to HashiCorp’s licensing decision for Terraform to no longer be open source, the Terraform community announced the creation of OpenTofu, as a fork of Terraform.

OpenTofu was created, as a fork of Terraform, to meet the evolving needs of modern infrastructure management, promote openness and collaboration, and foster innovation in the infrastructure as code ecosystem. With its community-driven development, open-source foundation, and commitment to compatibility and stability, OpenTofu stands as a testament to the power of collective effort and shared vision in advancing technology for the benefit of all.

OpenTofu is managed by the Linux Foundation

OpenTofu was created by forking the legacy MPL-licensed Terraform and is being maintained in the Linux Foundation. This means OpenTofu is managed similar to the way Linux is managed, with the Linux Foundation under the stewardship of multiple companies. This is done to ensure that OpenTofu stays truly open source and neutral from too much influence by any one company. As a part of the Linux Foundation, OpenTofu will be able to stay true to it’s original goals of: truly open source, community driven, impartial, layered and modular, and backwards compatible.

Working with OpenTofu

The core workflow of OpenTofu involves three steps: Write, Plan, and Apply. With OpenTofu being based on an earlier version of HashiCorp Terraform, this means that OpenTofu follows the same workflow process as Terraform.

1. Write – Users author infrastructure as code using their preferred editor, storing their work in version-controlled repositories.
2. Plan – Changes are previewed before applying, allowing for error detection and ensuring the configuration aligns with expectations.
3. Apply – Infrastructure is provisioned based on the defined configuration, with a final confirmation step to execute changes.

Migrating to OpenTofu from Terraform

In the dynamic landscape of infrastructure management, staying agile and adaptable is paramount. As organizations strive for greater efficiency, scalability, and collaboration in their infrastructure operations, the choice of tools becomes crucial. While Terraform has long been a cornerstone in the realm of infrastructure as code (IaC), the emergence of OpenTofu offers an intriguing alternative worth exploring.

But why migrate from Terraform to OpenTofu in the first place?

This question resonates with many organizations seeking to optimize their infrastructure workflows. While Terraform remains a powerful and widely-used tool, OpenTofu brings unique advantages to the table. From its open-source, community-driven development to its compatibility with Terraform configurations, OpenTofu presents an opportunity to leverage the strengths of Terraform while embracing the innovations and collaborative ethos of the OpenTofu ecosystem.

In this section, we’ll delve into the migration process from Terraform to OpenTofu, exploring the steps involved and highlighting the benefits that motivate organizations to make the transition. Whether it’s about harnessing the latest features, tapping into community-driven enhancements, or aligning with a broader vision of open infrastructure management, migrating to OpenTofu represents a strategic decision for organizations keen on embracing the future of infrastructure as code.

For those considering migrating from Terraform to OpenTofu, a seamless transition is possible with version compatibility and a structured migration guide:

1. Prepare – Ensure a disaster recovery plan is in place.
2. Apply Changes with Terraform – Finalize pending changes with Terraform before migrating.
3. Install OpenTofu – Follow installation instructions and verify compatibility.
4. Back Up State File – Backup the state file before migrating.
5. Initialize OpenTofu – Run initialization commands in the project directory.
6. Inspect Plan – Review the plan to ensure compatibility and expected changes.
7. Test Small Change – Execute a small, non-critical change to validate migration success.

Does OpenTofu work with all Terraform Providers?

One common question among users exploring OpenTofu as an alternative to Terraform is whether it supports all the providers that Terraform does. The answer to this question involves understanding how OpenTofu interacts with Terraform providers.

OpenTofu itself does not introduce its own set of providers. Instead, it relies on the existing ecosystem of Terraform providers. These providers have not undergone any alterations to their licenses, and the likelihood of such changes occurring is really low. Therefore, OpenTofu maintains compatibility with the current library of Terraform providers.

However, it’s essential to note that OpenTofu utilizes a separate registry from Terraform. While it works with the same providers, it operates within its own ecosystem. This separation allows OpenTofu to offer a distinct user experience while leveraging the familiar capabilities of Terraform providers.

OpenTofu works seamlessly with the existing Terraform providers, ensuring compatibility and consistency while providing users with a distinct infrastructure management solution.

OpenTofu Compatibility Promise

OpenTofu v1.x represents a stable platform for infrastructure management, with a commitment to maintaining compatibility throughout its releases. Here’s a summary of the compatibility promises made by OpenTofu:

1. Language Features: A large subset of OpenTofu language features will remain compatible across v1.x releases.
2. CLI Workflow Commands: A conservative subset of OpenTofu CLI workflow commands will be maintained for compatibility.
3. Wire Protocols: The wire protocols for communication between OpenTofu Core and providers, as well as for installation of providers and external modules, will remain consistent.
4. Module Compatibility: Modules written for OpenTofu v1.6 are intended to plan and apply successfully throughout the v1.x releases without required changes.
5. Automation Compatibility: Automation built around the defined workflow subset will work without changes in all future v1.x releases.
6. Provider Compatibility: Providers built against the documented wire protocol will be compatible with all future v1.x releases targeting the same operating system and architecture without modification or recompilation.

In essence, upgrades between v1.x releases are intended to be straightforward, requiring no changes to configurations, no extra commands for upgrade steps, and no adjustments to existing automation. OpenTofu v1.x series will be actively maintained for at least 18 months after v1.6, ensuring continued support and stability for users. Compatibility issues will be treated as bugs to be fixed, with any changes made with significant justification, such as addressing critical security problems or matching breaking changes to remote dependencies.

Use Cases of OpenTofu

OpenTofu emerges as a versatile and community-driven infrastructure as code (IaC) tool, offering a robust set of capabilities to address modern challenges in cloud infrastructure management. With its open-source nature and Linux Foundation stewardship, OpenTofu represents a compelling alternative to established solutions like Terraform. In this section, we delve into the diverse and impactful use cases of OpenTofu, showcasing its adaptability and effectiveness in various scenarios of infrastructure provisioning and management. From multi-cloud deployments to policy compliance enforcement and PaaS application setup, OpenTofu empowers users with the tools to streamline operations, enhance resilience, and foster innovation in their infrastructure environments. Let’s explore the wide array of possibilities that OpenTofu offers in revolutionizing the way we approach infrastructure management.

Multi-Cloud Deployment

Provisioning infrastructure across multiple clouds enhances fault tolerance but also introduces complexity. OpenTofu simplifies this by allowing the same workflow to manage multiple providers, streamlining management and orchestration for large-scale, multi-cloud infrastructures.

Application Infrastructure Deployment, Scaling, and Monitoring Tools

OpenTofu facilitates the deployment, scaling, and monitoring of infrastructure for multi-tier applications. It supports N-tier application architecture, enabling the management of resources in each tier while automatically handling dependencies between tiers.

Self-Service Clusters

Organizations can implement a “self-serve” infrastructure model using OpenTofu, empowering product teams to manage their own infrastructure efficiently. Standardized OpenTofu modules codify deployment and management practices, integrating seamlessly with ticketing systems for automated infrastructure requests.

Policy Compliance and Management

With OpenTofu, organizations can enforce policies on resource provisioning and usage, replacing manual ticket-based review processes with automated policy enforcement using frameworks like Sentinel.

PaaS Application Setup

OpenTofu can codify the setup required for Platform as a Service (PaaS) applications, streamlining configuration tasks such as DNS setup and content delivery network (CDN) integration.

Software Defined Networking

Automated configuration of Software Defined Networks (SDNs) with OpenTofu enables a shift from manual to automated workflows, reducing deployment times.

Kubernetes

OpenTofu supports the deployment and management of Kubernetes clusters and their resources.

Parallel Environments

OpenTofu facilitates the rapid creation and decommissioning of infrastructure for development, test, QA, and production environments, optimizing cost efficiency.

Software Demos

Users can utilize OpenTofu to create, provision, and bootstrap demos on various cloud providers, facilitating easy testing and scalability.

Conclusion

OpenTofu presents a compelling alternative to HashiCorp Terraform, offering an open-source, community-driven approach to infrastructure as code. With its diverse use cases and seamless migration process, OpenTofu empowers individuals, teams, and organizations to efficiently manage and provision infrastructure throughout its lifecycle.

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