Infrastructure-as-Code (IaC) is mainly about the management and provisioning of infrastructure through code. Instead of the conventional physical hardware configuration, IaC embeds in code the instructions of resource allocations and other details of infrastructure management. Not many may realize that all of these involve data management.
The use of the Terraform remote state, in particular, can be viewed from the perspective of data management, wherein accuracy, consistency, and efficiency are a must. In Terraform, the state files are important as they play a crucial role in monitoring resources. These files contain metadata, current state details, and other information useful in planning and applying changes to infrastructure. It helps to observe data science principles in working with these files.
Here’s a look at how data management principles are at play in IaC management with Terraform, especially with a remote backend involved.
Understanding remote state and remote backend
Before exploring the data management aspect of the Terraform remote backend, here’s an overview of the Terraform remote state and the use of a remote backend. A remote state is essentially the representation of the intended configuration. It is one of the two types of Terraform states, the other being the local state, which is stored in the local filesystem, particularly in the system where the Terraform command is executed.
By default, Terraform saves a state in a “terraform.tfstate” file on the local machine (local state). This file serves as the reference that enables the detection of discrepancies between the intended configuration and the actual deployment of resources. However, it would be difficult to rely on local states to do discrepancy detection, especially for organizations that operate in multiple locations. Thus, a remote state may be needed, and to do this organizations would need a remote backend
A remote backend is a shareable remote state that comes with the same capabilities as the local state, specifically the prevention of conflicts and inconsistencies. However, it provides the advantage of making state data available to all infrastructure management team members to enable synchronicity in the application of changes.
Single source of truth
One vital purpose of a remote state is to provide a single source of truth. It provides a centralized location for the storage of state and configuration data. It ensures that there is only one basis for the configuration deployment and the state in Terraform IaC management.
A state is a snapshot of the infrastructure and the resources being managed. Thus, there cannot be more than one version of it. The state is a critical aspect of Terraform’s operation because it enables the understanding of the current state of an infrastructure to support informed decision-making when it comes to the changes that need to be applied.
A remote state ensures data consistency, which also entails concurrency control. Having a remote backend imposes state locking or the prevention of the possibility of uncoordinated concurrent modifications to the infrastructure. This ensures that the application of changes relies on only a single source of truth, allowing only one process or, in some cases, one person to apply modifications to the infrastructure at any given time. This ensures the consistency of configuration data and precludes conflicts in the application of changes.
In connection with the principle of data consistency (single source of truth), the use of a remote state ensures that configuration changes are based on the latest state. This is critical especially when multiple DevOps team members are working on the configuration.
Here’s an example scenario: DevOps Member A creates a Terraform module for an S3 bucket (that is supposed to be publicly accessible) but erroneously restricts access by setting ACL to “private.” Meanwhile, Member B spots the error and sets ACL to “public-read.” Both of them are using local state. Member A returns and applies another change, but because his state is locally saved, he also re-applies the private ACL setting, not realizing this mistake because ACL was already made “public-read” by another member but they have different states stored locally in their respective devices. As such, access was restricted once again.
Data in an organization, especially as it pertains to infrastructure configuration, cannot be consistent if it is not based on the most recent information. This is particularly true when it comes to Terraform states. As such, it is advisable to consider using a remote backend instead of sticking to the default local state storage.
Using a remote state can also bolster data security. Remote backend solutions usually come with enhanced security features to protect sensitive information. They can provide encryption for passwords and other secrets to ensure state data integrity and confidentiality. They can also have access control systems to restrict access to authorized persons and processes.
Additionally, remotely storing state data provides the advantage of faster disaster recovery. With local states, technical issues affecting local devices can easily throw off the whole configuration chain. As shown in the example above, all it takes is for one un-updated local state file to cause inaccessibility and it may take some time before the team learns about and addresses the issue. Remote backends prevent these instances and they can also offer versioning to make it easy to track infrastructure state changes and quickly roll back to previous working states if issues are encountered.
One important benefit of having a remote state instead of saving it in a local machine is collaboration. Through a remote backend, the remote state is created in a centralized location that can be easily shared with multiple team members working on infrastructure configuration and management.
To be clear, though, collaboration here refers to different team members or teams working on the same configuration, not the use of a centralized state file to allow multiple teams to work with multiple infrastructures. After all, the Terraform state file is associated with a specific Terraform configuration, representing the state of the infrastructure described in the specific configuration.
In modern IT, proper data management goes beyond the collection, storage, and securing of data. Data exists where computing exists, so it makes perfect sense to look at things like infrastructure management with a data management lens. The use of a remote backend to take advantage of the remote state feature in Terraform IaC management is an example of how data management principles benefit various aspects of modern technology. Data should be consistent, up-to-date, secured, and available just like how infrastructure state data should be kept consistent, up-to-date, and securely and systematically made available to authorized users to avoid problems in infrastructure configuration and management.
About the author: Hazel Raoult is a freelance marketing writer and works with PRmention. She has 6+ years of experience in writing about business, entrepreneurship, marketing, and all things SaaS. Hazel loves to split her time between writing, editing, and hanging out with her family.