terraform/website/source/docs/configuration/providers.html.md

layout	page_title	sidebar_current	description
docs	Configuring Providers	docs-config-providers	Providers are responsible in Terraform for managing the lifecycle of a resource: create, read, update, delete.

Provider Configuration

Providers are responsible in Terraform for managing the lifecycle of a resource: create, read, update, delete.

Every resource in Terraform is mapped to a provider based on longest-prefix matching. For example the aws_instance resource type would map to the aws provider (if that exists).

Most providers require some sort of configuration to provide authentication information, endpoint URLs, etc. Provider configuration blocks are a way to set this information globally for all matching resources.

This page assumes you're familiar with the configuration syntax already.

Example

A provider configuration looks like the following:

provider "aws" {
	access_key = "foo"
	secret_key = "bar"
	region = "us-east-1"
}

Description

The provider block configures the provider of the given NAME. Multiple provider blocks can be used to configure multiple providers.

Terraform matches providers to resources by matching two criteria. Both criteria must be matched for a provider to manage a resource:

• They must share a common prefix. Longest matching prefixes are tried first. For example, aws_instance would choose the aws provider.

• The provider must report that it supports the given resource type. Providers internally tell Terraform the list of resources they support.

Within the block (the { }) is configuration for the resource. The configuration is dependent on the type, and is documented for each provider.

Multiple Provider Instances

You can define multiple instances of the same provider in order to support multiple regions, multiple hosts, etc. The primary use case for this for multiple cloud regions. Other use cases including targeting multiple Docker hosts, multiple Consul hosts, etc.

To define multiple provider instances, repeat the provider configuration multiple times, but set the alias field and name the provider. For example:

# The default provider
provider "aws" {
	# ...
}

# West coast region
provider "aws" {
	alias = "west"

	region = "us-west-2"
}

After naming a provider, you reference it in resources with the provider field:

resource "aws_instance" "foo" {
	provider = "aws.west"

	# ...
}

If a provider isn't specified, then the default provider configuration is used (the provider configuration with no alias set). The value of the provider field is TYPE.ALIAS, such as "aws.west" above.

Syntax

The full syntax is:

provider NAME {
	CONFIG ...
	[alias = ALIAS]
}

where CONFIG is:

KEY = VALUE

KEY {
	CONFIG
}