allow rds to assume this role

Terraform module to provision an RDS Aurora cluster for MySQL or Postgres.

Supports Amazon Aurora Serverless.

Tip

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Example of running atmos to manage infrastructure from our Quick Start tutorial.

Usage

For a complete example, see examples/complete.

For automated tests of the complete example using bats and Terratest (which tests and deploys the example on AWS), see test.

Basic example

module "rds_cluster_aurora_postgres" {
  source = "cloudposse/rds-cluster/aws"
  # Cloud Posse recommends pinning every module to a specific version
  # version     = "x.x.x"

  name            = "postgres"
  engine          = "aurora-postgresql"
  cluster_family  = "aurora-postgresql9.6"
  # 1 writer, 1 reader
  cluster_size    = 2
  # 1 writer, 3 reader
  # cluster_size    = 4
  # 1 writer, 5 reader
  # cluster_size    = 6
  namespace       = "eg"
  stage           = "dev"
  admin_user      = "admin1"
  admin_password  = "Test123456789"
  db_name         = "dbname"
  db_port         = 5432
  instance_type   = "db.r4.large"
  vpc_id          = "vpc-xxxxxxxx"
  security_groups = ["sg-xxxxxxxx"]
  subnets         = ["subnet-xxxxxxxx", "subnet-xxxxxxxx"]
  zone_id         = "Zxxxxxxxx"
}

Serverless Aurora MySQL 5.6

module "rds_cluster_aurora_mysql_serverless" {
  source = "cloudposse/rds-cluster/aws"
  # Cloud Posse recommends pinning every module to a specific version
  # version     = "x.x.x"
  namespace            = "eg"
  stage                = "dev"
  name                 = "db"
  engine               = "aurora"
  engine_mode          = "serverless"
  cluster_family       = "aurora5.6"
  cluster_size         = 0
  admin_user           = "admin1"
  admin_password       = "Test123456789"
  db_name              = "dbname"
  db_port              = 3306
  instance_type        = "db.t2.small"
  vpc_id               = "vpc-xxxxxxxx"
  security_groups      = ["sg-xxxxxxxx"]
  subnets              = ["subnet-xxxxxxxx", "subnet-xxxxxxxx"]
  zone_id              = "Zxxxxxxxx"
  enable_http_endpoint = true

  scaling_configuration = [
    {
      auto_pause               = true
      max_capacity             = 256
      min_capacity             = 2
      seconds_until_auto_pause = 300
    }
  ]
}

Serverless Aurora 2.07.1 MySQL 5.7

module "rds_cluster_aurora_mysql_serverless" {
  source = "cloudposse/rds-cluster/aws"
  # Cloud Posse recommends pinning every module to a specific version
  # version     = "x.x.x"
  namespace            = "eg"
  stage                = "dev"
  name                 = "db"
  engine               = "aurora-mysql"
  engine_mode          = "serverless"
  engine_version       = "5.7.mysql_aurora.2.07.1"
  cluster_family       = "aurora-mysql5.7"
  cluster_size         = 0
  admin_user           = "admin1"
  admin_password       = "Test123456789"
  db_name              = "dbname"
  db_port              = 3306
  vpc_id               = "vpc-xxxxxxxx"
  security_groups      = ["sg-xxxxxxxx"]
  subnets              = ["subnet-xxxxxxxx", "subnet-xxxxxxxx"]
  zone_id              = "Zxxxxxxxx"
  enable_http_endpoint = true

  scaling_configuration = [
    {
      auto_pause               = true
      max_capacity             = 16
      min_capacity             = 1
      seconds_until_auto_pause = 300
      timeout_action           = "ForceApplyCapacityChange"
    }
  ]
}

With cluster parameters

module "rds_cluster_aurora_mysql" {
  source = "cloudposse/rds-cluster/aws"
  # Cloud Posse recommends pinning every module to a specific version
  # version     = "x.x.x"
  engine          = "aurora"
  cluster_family  = "aurora-mysql5.7"
  cluster_size    = 2
  namespace       = "eg"
  stage           = "dev"
  name            = "db"
  admin_user      = "admin1"
  admin_password  = "Test123456789"
  db_name         = "dbname"
  instance_type   = "db.t2.small"
  vpc_id          = "vpc-xxxxxxx"
  security_groups = ["sg-xxxxxxxx"]
  subnets         = ["subnet-xxxxxxxx", "subnet-xxxxxxxx"]
  zone_id         = "Zxxxxxxxx"

  cluster_parameters = [
    {
      name  = "character_set_client"
      value = "utf8"
    },
    {
      name  = "character_set_connection"
      value = "utf8"
    },
    {
      name  = "character_set_database"
      value = "utf8"
    },
    {
      name  = "character_set_results"
      value = "utf8"
    },
    {
      name  = "character_set_server"
      value = "utf8"
    },
    {
      name  = "collation_connection"
      value = "utf8_bin"
    },
    {
      name  = "collation_server"
      value = "utf8_bin"
    },
    {
      name         = "lower_case_table_names"
      value        = "1"
      apply_method = "pending-reboot"
    },
    {
      name         = "skip-character-set-client-handshake"
      value        = "1"
      apply_method = "pending-reboot"
    }
  ]
}

With enhanced monitoring

# create IAM role for monitoring
resource "aws_iam_role" "enhanced_monitoring" {
  name               = "rds-cluster-example-1"
  assume_role_policy = data.aws_iam_policy_document.enhanced_monitoring.json
}

# Attach Amazon's managed policy for RDS enhanced monitoring
resource "aws_iam_role_policy_attachment" "enhanced_monitoring" {
  role       = aws_iam_role.enhanced_monitoring.name
  policy_arn = "arn:aws:iam::aws:policy/service-role/AmazonRDSEnhancedMonitoringRole"
}

# allow rds to assume this role
data "aws_iam_policy_document" "enhanced_monitoring" {
  statement {
      actions = [
      "sts:AssumeRole",
    ]

    effect = "Allow"

    principals {
      type        = "Service"
      identifiers = ["monitoring.rds.amazonaws.com"]
    }
  }
}

module "rds_cluster_aurora_postgres" {
  source = "cloudposse/rds-cluster/aws"
  # Cloud Posse recommends pinning every module to a specific version
  # version     = "x.x.x"
  engine          = "aurora-postgresql"
  cluster_family  = "aurora-postgresql9.6"
  cluster_size    = 2
  namespace       = "eg"
  stage           = "dev"
  name            = "db"
  admin_user      = "admin1"
  admin_password  = "Test123456789"
  db_name         = "dbname"
  db_port         = 5432
  instance_type   = "db.r4.large"
  vpc_id          = "vpc-xxxxxxx"
  security_groups = ["sg-xxxxxxxx"]
  subnets         = ["subnet-xxxxxxxx", "subnet-xxxxxxxx"]
  zone_id         = "Zxxxxxxxx"

  # enable monitoring every 30 seconds
  rds_monitoring_interval = 30

  # reference iam role created above
  rds_monitoring_role_arn = aws_iam_role.enhanced_monitoring.arn
}

Examples

Review the complete example to see how to use this module.

Requirements

Providers

Modules

Resources

Inputs

list(object({
    apply_method = string
    name         = string
    value        = string
  }))

{
  "additional_tag_map": {},
  "attributes": [],
  "delimiter": null,
  "descriptor_formats": {},
  "enabled": true,
  "environment": null,
  "id_length_limit": null,
  "label_key_case": null,
  "label_order": [],
  "label_value_case": null,
  "labels_as_tags": [
    "unset"
  ],
  "name": null,
  "namespace": null,
  "regex_replace_chars": null,
  "stage": null,
  "tags": {},
  "tenant": null
}

[
  "enhanced-monitoring"
]

list(object({
    apply_method = string
    name         = string
    value        = string
  }))

[
  "default"
]

list(object({
    source_cluster_identifier  = string
    restore_type               = optional(string, "copy-on-write")
    use_latest_restorable_time = optional(bool, true)
    restore_to_time            = optional(string, null)
  }))

object({
    bucket_name           = string
    bucket_prefix         = string
    ingestion_role        = string
    source_engine         = string
    source_engine_version = string
  })

list(object({
    auto_pause               = bool
    max_capacity             = number
    min_capacity             = number
    seconds_until_auto_pause = number
    timeout_action           = string
  }))

object({
    min_capacity             = number
    max_capacity             = number
    seconds_until_auto_pause = optional(number, null)
  })

list(object({
    create = string
    update = string
    delete = string
  }))

Outputs

Related Projects

Check out these related projects.

• terraform-aws-rds - Terraform module to provision AWS RDS instances
• terraform-aws-rds-cloudwatch-sns-alarms - Terraform module that configures important RDS alerts using CloudWatch and sends them to an SNS topic

✨ Contributing

This project is under active development, and we encourage contributions from our community.

Many thanks to our outstanding contributors:

For 🐛 bug reports & feature requests, please use the issue tracker.

In general, PRs are welcome. We follow the typical "fork-and-pull" Git workflow.

1. Review our Code of Conduct and Contributor Guidelines.
2. Fork the repo on GitHub
3. Clone the project to your own machine
4. Commit changes to your own branch
5. Push your work back up to your fork
6. Submit a Pull Request so that we can review your changes

NOTE: Be sure to merge the latest changes from "upstream" before making a pull request!

Running Terraform Tests

We use Atmos to streamline how Terraform tests are run. It centralizes configuration and wraps common test workflows with easy-to-use commands.

All tests are located in the test/ folder.

Under the hood, tests are powered by Terratest together with our internal Test Helpers library, providing robust infrastructure validation.

Setup dependencies:

• Install Atmos (installation guide)
• Install Go 1.24+ or newer
• Install Terraform or OpenTofu

To run tests:

• Run all tests:

  atmos test run
  

• Clean up test artifacts:

  atmos test clean
  

• Explore additional test options:

  atmos test --help
  

The configuration for test commands is centrally managed. To review what's being imported, see the atmos.yaml file.

Learn more about our automated testing in our documentation or implementing custom commands with atmos.

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License

Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements.  See the NOTICE file
distributed with this work for additional information
regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at

  https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing,
software distributed under the License is distributed on an
"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License.

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