Module: `rds-cluster-instance-group`

Terraform module to provision an RDS Aurora instance group for MySQL or Postgres along with a dedicated endpoint.

Use this module together with our terraform-aws-rds-cluster to provision pools of RDS instances. This is useful for creating reporting clusters that don't impact the production databases.

Supports Amazon Aurora Serverless.

Usage

Basic example

module "rds_cluster_replicas" {
  source             = "git::https://github.com/cloudposse/terraform-aws-rds-cluster-instance-group.git?ref=master"
  name               = "postgres"
  namespace          = "eg"
  stage              = "dev"
  attributes         = ["replicas"]
  cluster_identifier = "eg-dev-db"
  cluster_size       = "2"
  db_port            = "5432"
  instance_type      = "db.r4.large"
  vpc_id             = "vpc-xxxxxxxx"
  security_groups    = ["sg-xxxxxxxx"]
  subnets            = ["subnet-xxxxxxxx", "subnet-xxxxxxxx"]
  zone_id            = "Zxxxxxxxx"
}

With cluster parameters

module "rds_cluster_reporting" {
  source             = "git::https://github.com/cloudposse/terraform-aws-rds-cluster-instance-group.git?ref=master"
  cluster_size       = "2"
  namespace          = "eg"
  stage              = "dev"
  name               = "db"
  attributes         = ["reporting"]
  cluster_identifier = "eg-dev-db"
  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 = "uft8_bin"
    },
    {
      name  = "collation_server"
      value = "uft8_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_reporting" {
  source             = "git::https://github.com/cloudposse/terraform-aws-rds-cluster-instance-group.git?ref=master"
  cluster_size       = "2"
  namespace          = "eg"
  stage              = "dev"
  name               = "db"
  attributes         = ["reporting"]
  cluster_identifier = "eg-dev-db"
  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}"
}

Requirements

No requirements.

Providers

Name	Version
aws	n/a

Modules

Name	Source	Version
dns	git::https://github.com/cloudposse/terraform-aws-route53-cluster-hostname.git	tags/0.2.5
label	git::https://github.com/cloudposse/terraform-null-label.git	tags/0.3.5

Resources

Name	Type
aws_db_parameter_group.default	resource
aws_rds_cluster_endpoint.default	resource
aws_rds_cluster_instance.default	resource
aws_security_group.default	resource
aws_security_group_rule.allow_egress	resource
aws_security_group_rule.allow_ingress	resource
aws_security_group_rule.allow_ingress_cidr	resource
aws_rds_cluster.default	data source

Inputs

Name	Description	Type	Default	Required
allowed_cidr_blocks	List of CIDR blocks allowed to access	`list`	`[]`	no
apply_immediately	Specifies whether any cluster modifications are applied immediately, or during the next maintenance window	`string`	`"true"`	no
attributes	Additional attributes (e.g. `1`)	`list`	`[ "replicas" ]`	no
cluster_family	The family of the DB cluster parameter group	`string`	`"aurora5.6"`	no
cluster_identifier	The cluster identifier	`string`	n/a	yes
cluster_size	Number of DB instances to create in the cluster	`string`	`"2"`	no
custom_endpoint_type	The type of the endpoint. One of: READER, ANY	`string`	`"READER"`	no
db_port	Database port	`string`	`"3306"`	no
db_subnet_group_name	A DB subnet group to associate with this DB instance. NOTE: This must match the db_subnet_group_name of the attached aws_rds_cluster.	`string`	`""`	no
delimiter	Delimiter to be used between `name`, `namespace`, `stage` and `attributes`	`string`	`"-"`	no
enabled	Set to false to prevent the module from creating any resources	`string`	`"true"`	no
engine	The name of the database engine to be used for this DB cluster. Valid values: `aurora`, `aurora-mysql`, `aurora-postgresql`	`string`	`"aurora"`	no
instance_parameters	List of DB instance parameters to apply	`list`	`[]`	no
instance_type	Instance type to use	`string`	`"db.t2.small"`	no
name	Name of the application	`string`	n/a	yes
namespace	Namespace (e.g. `eg` or `cp`)	`string`	n/a	yes
promotion_tier	Failover Priority setting on instance level. The reader who has lower tier has higher priority to get promoted to writer (values can range from 0-15).	`string`	`"15"`	no
publicly_accessible	Set to true if you want your cluster to be publicly accessible (such as via QuickSight)	`string`	`"false"`	no
rds_monitoring_interval	Interval in seconds that metrics are collected, 0 to disable (values can only be 0, 1, 5, 10, 15, 30, 60)	`string`	`"0"`	no
rds_monitoring_role_arn	The ARN for the IAM role that can send monitoring metrics to CloudWatch Logs	`string`	`""`	no
security_group_ids	The IDs of the security groups from which to allow `ingress` traffic to the DB instances	`list`	`[]`	no
security_groups	List of security groups to be allowed to connect to the DB instances	`list`	`[]`	no
stage	Stage (e.g. `prod`, `dev`, `staging`)	`string`	n/a	yes
storage_encrypted	Specifies whether the DB cluster is encrypted. The default is `false` for `provisioned` `engine_mode` and `true` for `serverless` `engine_mode`	`string`	`"true"`	no
subnets	List of VPC subnet IDs	`list`	n/a	yes
tags	Additional tags (e.g. map(`BusinessUnit`,`XYZ`)	`map`	`{}`	no
vpc_id	VPC ID to create the cluster in (e.g. `vpc-a22222ee`)	`string`	n/a	yes
zone_id	Route53 parent zone ID. If provided (not empty), the module will create sub-domain DNS record for the cluster endpoint	`string`	`""`	no

Outputs

Name	Description
endpoint	The endpoint for the Aurora cluster, automatically load-balanced across replicas
hostname	The DNS address for the endpoint of the Aurora cluster

Module: rds-cluster-instance-group

Usage​

Requirements​

Providers​

Modules​

Resources​

Inputs​

Outputs​