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intro Terraform Remote gettingstarted-remote We've now seen how to build, change, and destroy infrastructure from a local machine. However, you can use Atlas by HashiCorp to run Terraform remotely to version and audit the history of your infrastructure.

Remote Backends

We've now seen how to build, change, and destroy infrastructure from a local machine. This is great for testing and development, however in production environments it is more responsible to run Terraform remotely and store a master Terraform state remotely.

Terraform supports a feature known as remote backends to support this. Backends are the recommended way to use Terraform in a team environment.

Depending on the features you wish to use, Terraform has multiple remote backend options. You could use Consul for state storage, locking, and environments. This is a free and open source option. You can use S3 which only supports state storage, for a low cost and minimally featured solution.

Terraform Enterprise is HashiCorp's commercial solution and also acts as a remote backend. Terraform Enterprise allows teams to easily version, audit, and collaborate on infrastructure changes. Each proposed change generates a Terraform plan which can be reviewed and collaborated on as a team. When a proposed change is accepted, the Terraform logs are stored, resulting in a linear history of infrastructure states to help with auditing and policy enforcement. Additional benefits to running Terraform remotely include moving access credentials off of developer machines and releasing local machines from long-running Terraform processes.

How to Store State Remotely

First, we'll use Consul as our backend. Consul is a free and open source solution that provides state storage, locking, and environments. It is a great way to get started with Terraform backends.

We'll use the demo Consul server for this guide. This should not be used for real data. Additionally, the demo server doesn't permit locking. If you want to play with state locking, you'll have to run your own Consul server or use a backend that supports locking.

First, configure the backend in your configuration:

terraform {
  backend "consul" {
    address = "demo.consul.io"
    path    = "getting-started-RANDOMSTRING"
    lock    = false
  }
}

Please replace "RANDOMSTRING" with some random text. The demo server is public and we want to try to avoid overlapping with someone else running through the getting started guide.

The backend section configures the backend you want to use. After configuring a backend, run terraform init to setup Terraform. It should ask if you want to migrate your state to Consul. Say "yes" and Terraform will copy your state.

Now, if you run terraform plan, Terraform should state that there are no changes:

$ terraform plan
...

No changes. Infrastructure is up-to-date.

This means that Terraform did not detect any differences between your
configuration and real physical resources that exist. As a result, Terraform
doesn't need to do anything.

Terraform is now storing your state remotely in Consul. Remote state storage makes collaboration easier and keeps state and secret information off your local disk. Remote state is loaded only in memory when it is used.

If you want to move back to local state, you can remove the backend configuration block from your configuration and run terraform init again. Terraform will once again ask if you want to migrate your state back to local.

Terraform Enterprise

HashiCorp (the makers of Terraform) also provide a commercial solution which functions as a Terraform backend as well as enabling many other features such as remote apply, run history, state history, state diffing, and more.

This section will guide you through a demo of Terraform Enterprise. Note that this is commercial software. If you are not interested at this time, you may skip this section.

First, create an account here unless you already have one.

Terraform uses your access token to securely communicate with Terraform Enterprise. To generate a token: select your username in the left side navigation menu, click "Accounts Settings", "click "Tokens", then click "Generate".

For the purposes of this tutorial you can use this token by exporting it to your local shell session:

$ export ATLAS_TOKEN=ATLAS_ACCESS_TOKEN

Replace ATLAS_ACCESS_TOKEN with the token generated earlier. Next, configure the Terraform Enterprise backend:

terraform {
  backend "atlas" {
    name = "USERNAME/getting-started"
  }
}

Replace USERNAME with your Terraform Enterprise username. Note that the backend name is "atlas" for legacy reasons and will be renamed soon.

Remember to run terraform init. At this point, Terraform is using Terraform Enterprise for everything shown before with Consul. Next, we'll show you some additional functionality Terraform Enterprise enables.

Before you push your Terraform configuration to Terraform Enterprise you'll need to start a local version control system with at least one commit. Here is an example using git.

$ git init
$ git add example.tf
$ git commit -m "init commit"

Next, push your Terraform configuration:

$ terraform push

This will automatically trigger a terraform plan, which you can review in the Terraform page. If the plan looks correct, hit "Confirm & Apply" to execute the infrastructure changes.

Running Terraform in Terraform Enterprise creates a complete history of infrastructure changes, a sort of version control for infrastructure. Similar to application version control systems such as Git or Subversion, this makes changes to infrastructure an auditable, repeatable, and collaborative process. With so much relying on the stability of your infrastructure, version control is a responsible choice for minimizing downtime.

Next

You now know how to create, modify, destroy, version, and collaborate on infrastructure. With these building blocks, you can effectively experiment with any part of Terraform.

We've now concluded the getting started guide, however there are a number of next steps to get started with Terraform.