When using a remote backend that requires authentication, what does HashiCorp recommend?

Using partial configuration to load credentials outside of Terraform is the recommended approach when utilizing a remote backend that requires authentication. This method enhances security by not embedding sensitive information directly in the Terraform configuration files, which can be stored in version control systems and potentially exposed.

By managing credentials outside of Terraform, you can utilize various mechanisms to provide those credentials dynamically at runtime. This may involve using configuration management tools, secret management solutions, or environment-specific credential stores, allowing for greater flexibility and security in handling sensitive information. It also aligns with the principle of least privilege by minimizing the risk of exposing credentials within the codebase.

This approach also facilitates seamless transitions between different environments, as you can configure the necessary credentials through external means without the need to alter the Terraform code itself. It creates a cleaner and more maintainable codebase, separating infrastructure management from sensitive data management, which is in line with best practices in software development and operations.