Collaboration on infrastructure projects can be a real pain. You have teams working on the same setups. There is a risk of conflicts, wasted work, and a whole lot of headaches when you try to sync what each team is working on. This is where Terraform remote state comes into play. It lets your team work together with ease, avoids conflicts, and keeps everyone on the same page. In this article, we will cover the ins and outs of Terraform remote state and show you how you can put it to work on your projects.
Understanding Terraform State
Before diving into the specifics of remote state, it’s key to understand what Terraform state is. At its core, Terraform state is a snapshot of your infrastructure. When you run Terraform, it creates a state file that keeps track of what resources have been built or changed, so it knows what’s happening. This file is a crucial part of how Terraform works.
Think of the state file as a map. It shows what is built and how it all fits together. Without this map, Terraform wouldn’t know what exists already. This would make changes to your infrastructure risky and hard to manage. In other words, your state file is critical.
The Default Local State
By default, Terraform saves the state file as a terraform.tfstate file in the same directory as your configuration files. This works well when you’re working on small projects or if you’re the only person working on a project.
But with teams, a local state file will cause problems. What happens if two people try to change the state at once? What if someone loses their state file? The local state isn’t built for collaboration.
The Need for Remote State
As teams grow, so does the need to share the state in a more organized way. This is where Terraform remote state becomes very helpful. Remote state stores your state in a place that everyone on your team can reach. This could be a cloud storage service, a database, or even a purpose-built tool.
Why Local State Isn’t Enough
Local state has some real issues:
* Risk of Data Loss: Local state files are saved on your own computer. If your computer fails or you lose the file, your infrastructure could be compromised.
* Collaboration Problems: When more than one person is working on the same code, the state file can get overwritten, and that can lead to conflicts and errors.
* Security Issues: Saving state in a file on your computer means it’s not protected. This is a risk if you’re working with sensitive infrastructure data.
Benefits of Using Remote State
Remote state fixes all the problems of using local state and offers a lot of benefits:
* Improved Collaboration: With remote state, many people can work on the same infrastructure at once with less risk of conflict.
* Better Security: Remote backends often have more security features built in, like access control and encryption.
* Data Backup and Recovery: Remote state storage options offer better data backup and restore choices so that if anything goes wrong, it’s easy to recover.
* State Locking: Many remote backends have a built-in feature called state locking. This means that when one person is making changes, other people can’t, and this helps prevent conflicts.
How Terraform Remote State Works
Terraform remote state works by moving the state file from a local computer to a remote location. This remote location is known as the backend. When you use a remote backend, Terraform does not save the state file locally but instead sends it to this backend.
Setting up the Remote Backend
To set up a remote backend, you must use a terraform block in your configuration. Here’s the basic idea:
terraform {
backend "..." {
# Configuration options go here
}
}
The backend block has a name that shows the kind of storage service you want to use, like s3 for Amazon S3 or azurerm for Azure Storage. After setting up a backend, Terraform will save your state in the remote location instead of your local computer.
Common Remote Backends
There are a lot of choices for remote backends. Each has its own way of doing things, features, and how they set up. Here are some of the most common ones:
- Amazon S3: S3 is a simple and easy to use storage system provided by Amazon. It’s cheap and offers features like versioning. For better security, it works well with encryption and access controls.
- Azure Storage: Azure Storage provides the same kind of service as Amazon S3. It stores state files as blobs in a container. It has features like state locking to ensure safety when teams are working on the same resources.
- Google Cloud Storage: Similar to S3 and Azure Storage, Google Cloud Storage stores state files in a bucket. It is another low-cost way to keep your state file safe.
- HashiCorp Terraform Cloud: This is the official product from the makers of Terraform. It provides a complete solution for saving state, collaboration, and workflows.
- Consul: Consul is a service mesh that also can be used to manage and store state. This may be suitable for teams already using it.
- PostgreSQL: PostgreSQL is an open-source database that can be used to store state. This approach might be used by teams already using it for other operations and who want to take advantage of its advanced data management tools.
Configuring a Remote Backend
Let’s look at examples of configuring a remote backend with a few of these options.
Amazon S3
To set up S3 as a remote backend, you’d add code like this to your terraform block:
terraform {
backend "s3" {
bucket = "my-terraform-state-bucket"
key = "path/to/my/terraform.tfstate"
region = "us-west-2"
}
}
In this code, the bucket parameter is where your state file will be saved in S3. The key shows the path to your state file, and region is where your bucket is.
Azure Storage
To set up Azure Storage as your remote backend, you’ll use a code block like this:
terraform {
backend "azurerm" {
resource_group_name = "my-resource-group"
storage_account_name = "mystorageaccount"
container_name = "mycontainer"
key = "path/to/my/terraform.tfstate"
}
}
Here, resource_group_name is the Azure Resource Group to save to, storage_account_name is the name of the storage account to use, and container_name is the blob container within that account to save to. key is the blob name, just as it is in S3.
Google Cloud Storage
To set up Google Cloud Storage, use a code block like this:
terraform {
backend "gcs" {
bucket = "my-terraform-state-bucket"
prefix = "path/to/my/terraform"
}
}
Here, bucket is your Google Cloud Storage bucket, and the prefix sets the path to the state file within the bucket.
HashiCorp Terraform Cloud
To set up Terraform Cloud as your remote backend, your configuration will look something like this:
terraform {
cloud {
organization = "your-org-name"
workspaces {
name = "your-workspace-name"
}
}
}
Here, organization shows the organization in Terraform Cloud, and workspaces shows which workspace to link to this setup.
Initializing the Backend
After setting up the backend in your code, you need to run terraform init. This command initializes your working directory and sets up the remote backend. Terraform will ask you to confirm the configuration to make sure you want to make the change.
Once it’s done, Terraform will start to save the state file in your chosen remote backend, and that’s it. Now you have all the benefits of a remote state.
Best Practices for Using Remote State
Setting up remote state isn’t enough, you also need to follow best practices to make the most of it. Here are some tips for making the most out of the remote state:
Secure Your Backend
It’s important to keep your remote backend safe, because it contains sensitive information about your infrastructure. Here are some key steps:
* Access Control: Make sure that only authorized people can access the remote backend. Use the identity and access management tools that your backend provides to limit who can do what.
* Encryption: Use encryption to protect your state file while it’s in transit and at rest. Most backends offer features to encrypt state at rest by default.
* Network Security: Limit who can access the remote backend by limiting it to specific networks or IPs. Make sure the access is restricted and not openly available.
Manage Secrets Carefully
Do not store secrets directly in your state file. Use a secure secrets management solution, like HashiCorp Vault, or the secrets features of your cloud provider, and use Terraform to get the secrets when you need them.
Use State Locking
Enable state locking to keep anyone from making changes at the same time. If someone is making changes, state locking will keep other people from modifying the state at the same time, and this prevents conflicts.
Version Your State
Use the versioning feature if it is available in your backend to save old versions of your state files. This lets you go back to a working state if needed, and this can be useful when you need to roll back from a failed deployment.
Keep Your State File Simple
Keep the state file as simple as possible to ensure that it’s easy to manage. This means that your configuration should be modular, broken down into small parts, so it’s easy to maintain. Make sure that the code is easy to understand. If your configuration gets too big, that can impact performance, so think about how you’ll break up your configuration files.
Regularly Backup Your State
Even with remote backends, it is always a good idea to regularly back up your state file. This acts as a safety net, and in case you need to restore your state quickly. Most of the popular backend storage solutions have options for backing up or restoring.
Adopt a Standard Workflow
Make sure that you and your team follow the same process. The workflow should include regular state pulls, so everyone is working from the newest state file, planning, which provides a view of how a deployment will look, and making sure to apply changes and not override each other’s deployments.
Dealing with Common Issues
While remote state can make managing your infrastructure much simpler, there are still some issues that teams might face, and knowing how to deal with them is key to managing your work effectively.
State Locking Errors
State locking errors are a common problem when you use remote state. They happen when a lock on the state file isn’t released properly. It can happen if someone exits or closes Terraform unexpectedly before it has a chance to finish what it’s doing. If you get a locking error, try to find the person with the lock, and see if you can get them to unlock it or release it, and then you’ll be able to continue. Most remote backends have commands that can help you manually unlock it.
State Corruption
State corruption can happen because of many reasons such as network issues, errors in configuration files, or mistakes when saving. If that happens, use versioning to roll back to a good version. If you don’t have versioning turned on, you might need to do a manual import of the existing resources to get the system working again.
Migration to a New Backend
Sometimes you’ll want to migrate your remote backend. If you do, you’ll have to use the terraform init -migrate-state command to move from one backend to another. It’s also good to test this process in a safe, non-production system before moving your production system.
Advanced Remote State Usage
Now that you know the basics, let’s explore some more complex ways of using remote state. These advanced approaches let you use remote state in many different ways for a large, complex infrastructure.
State Data Sources
Terraform data sources allow you to pull information from external sources. You can pull information about the remote state from other projects. This is useful for when you want to use resources from one project in another. For example, you can pull the ID of a network from a shared network project into a server project using a data source for remote state.
Here’s an example:
data "terraform_remote_state" "network" {
backend = "s3"
config = {
bucket = "my-shared-network-bucket"
key = "path/to/network.tfstate"
region = "us-west-2"
}
}
resource "aws_instance" "my_server" {
subnet_id = data.terraform_remote_state.network.outputs.subnet_id
ami = "ami-xxxxxxxxxxxxxxxxx"
instance_type = "t2.micro"
}
In the code above, the terraform_remote_state data source pulls information from the network project. The subnet_id variable gets its value from the remote state output. This lets you use the network from one project in the resources of another project without having to duplicate the code.
Multi-Environment State Management
Using the same remote backend for every environment, such as dev, test, and prod, is not advised. It can cause collisions, if they all use the same state file, so each environment should have its own state file.
You can organize this in multiple ways:
* **Separate Backends:** Each environment can use its own remote backend. This can be good for projects where the environments are managed completely separately.
* **Prefixes:** Use a single remote backend and use a different file path or directory prefix in your backend configuration for each environment. This is usually the preferred method because it is simple, and you can manage everything in the same bucket.
* **Workspaces:** Terraform workspaces are named environments within the same configuration, and they use the same backend. This can be good for teams that want to deploy different variations of the same configuration to different systems.
Here is an example of how you can manage multi environment using the single bucket, multiple prefixes approach:
terraform {
backend "s3" {
bucket = "my-terraform-state-bucket"
key = "${var.environment}/path/to/my/terraform.tfstate"
region = "us-west-2"
}
}
variable "environment" {
type = string
description = "The target environment: dev, test, prod."
default = "dev"
}
Here, the key parameter uses a variable named environment to create a unique path for each environment’s state file.
State Sharing and Collaboration Workflows
Terraform remote state does not only improve security and backup for your state files. It also enables complex collaboration workflows, which help teams work together more efficiently.
When multiple people are working on the same infrastructure, managing changes is hard. With remote state, teams can use it to do change reviews and manage how they deploy infrastructure.
Here are some key steps for a solid collaboration workflow:
* **Branching:** Use feature branches for all infrastructure changes. This keeps changes separate from your main branch until the changes are ready.
* **Pull Requests:** Do a code review for every change by opening a pull request. This helps to find issues before you push your changes.
* **Planning:** After you have your change approved, use the `terraform plan` command to preview changes before applying them.
* **Applying Changes:** After planning, apply the changes only if you’re sure. Make sure to communicate to your team before doing this, to prevent people from running deployments at the same time and potentially causing conflicts.
Making the Move to Remote State
If you’re using local state, there are some steps you must follow to make the change over to remote state. This process will require some planning and care to keep your current infrastructure working during the change. Here is how you can move to a remote state:
1. Choose Your Backend
First, choose the remote backend that works best for your team. S3 and Azure Storage are popular and easy to set up, but Terraform Cloud can be the most helpful if you want to take advantage of its automation features.
2. Set Up the Backend
Follow the set up instructions for your chosen backend. This will include creating the bucket, container, or other storage resource, and setting up the right permissions.
3. Add the Backend Code to your Configuration
Add the backend configuration as we showed earlier to your terraform block in your main terraform file.
4. Initialize Terraform
Run terraform init to initialize your working directory and set up the remote backend. Terraform might ask you to confirm that you want to move your state file to remote storage.
5. Verify Your Configuration
After initialization, run a terraform plan command to check that everything is working correctly.
6. Secure Your Backend
Ensure that your backend is set up securely, by setting access control and data encryption.
7. Make it a Team Policy
Make sure that you set out guidelines and policies to ensure that all team members follow the remote state setup you have made.
8. Backup your Local State
Before moving, back up your local state. You may need it if something goes wrong during the change.
The Future of Terraform State Management
Terraform state management is always evolving as more sophisticated features are being made. Here are some trends that you may want to pay attention to:
Improved State Locking
State locking features in current systems still have issues and often can be a pain to resolve, especially when they don’t release correctly after a deployment is complete. Expect to see improved locking features with better error recovery and better ways to deal with manual unlocks.
Advanced State Management Tools
Tools to help with more complex state management are becoming more common. This will include state visualization tools, better state migration tools, and ways to analyze state history and changes over time.
Better Security Features
Security is a key area for growth. Remote backends will continue to get better security with more encryption options, access control, and better tools to manage secrets.
Better Integrations with Other Tools
Expect to see better integrations with related technologies for managing infrastructures like cloud providers, secrets management systems, and automated deployment pipelines. This will make the complete infrastructure management setup easy to work with.
Is Terraform Remote State Really Worth It?
The use of Terraform remote state is essential when you’re working in a team. The pain, chaos, and risks associated with local state management are too severe for any team to ignore. By taking a strategic approach with remote state, your team will have a safe, organized, and collaborative approach to infrastructure management.
This approach won’t only enhance the collaboration of your team; but it will also improve your security and offer better data protection. By following the best practices outlined here, you can make the most of Terraform’s remote state features to bring more reliability and scalability to your infrastructure. It’s a move that every modern DevOps team should consider.