AWS RDS Aurora Terraform module

Terraform module which creates AWS RDS Aurora resources.

Available Features

• Autoscaling of read-replicas
• Global cluster
• Enhanced monitoring
• Serverless cluster (v1 and v2)
• Import from S3
• Fine grained control of individual cluster instances
• Custom endpoints
• RDS multi-AZ support (not Aurora)

Usage

module "cluster" {
  source  = "terraform-aws-modules/rds-aurora/aws"

  name           = "test-aurora-db-postgres96"
  engine         = "aurora-postgresql"
  engine_version = "14.5"
  instance_class = "db.r6g.large"
  instances = {
    one = {}
    2 = {
      instance_class = "db.r6g.2xlarge"
    }
  }

  vpc_id               = "vpc-12345678"
  db_subnet_group_name = "db-subnet-group"
  security_group_rules = {
    ex1_ingress = {
      cidr_blocks = ["10.20.0.0/20"]
    }
    ex1_ingress = {
      source_security_group_id = "sg-12345678"
    }
  }

  storage_encrypted   = true
  apply_immediately   = true
  monitoring_interval = 10

  enabled_cloudwatch_logs_exports = ["postgresql"]

  tags = {
    Environment = "dev"
    Terraform   = "true"
  }
}

Cluster Instance Configuration

There are a couple different configuration methods that can be used to create instances within the cluster:

ℹ️ Only the pertinent attributes are shown for brevity

1. Create homogenous cluster of any number of instances

• Resources created:
  • Writer: 1
  • Reader(s): 2

  instance_class = "db.r6g.large"
  instances = {
    one   = {}
    two   = {}
    three = {}
  }

2. Create homogenous cluster of instances w/ autoscaling enabled. This is redundant and we'll show why in the next example.

• Resources created:
  • Writer: 1
  • Reader(s):
    • At least 4 readers (2 created directly, 2 created by appautoscaling)
    • At most 7 reader instances (2 created directly, 5 created by appautoscaling)

ℹ️ Autoscaling uses the instance class specified by instance_class.

  instance_class = "db.r6g.large"
  instances = {
    one   = {}
    two   = {}
    three = {}
  }

  autoscaling_enabled      = true
  autoscaling_min_capacity = 2
  autoscaling_max_capacity = 5

3. Create homogeneous cluster scaled via autoscaling. At least one instance (writer) is required

• Resources created:
  • Writer: 1
  • Reader(s):
    • At least 1 reader
    • At most 5 readers

  instance_class = "db.r6g.large"
  instances = {
    one = {}
  }

  autoscaling_enabled      = true
  autoscaling_min_capacity = 1
  autoscaling_max_capacity = 5

4. Create heterogenous cluster to support mixed-use workloads

   It is common in this configuration to independently control the instance promotion_tier paired with endpoints to create custom endpoints directed at select instances or instance groups.

• Resources created:
  • Writer: 1
  • Readers: 2

  instance_class = "db.r5.large"
  instances = {
    one = {
      instance_class      = "db.r5.2xlarge"
      publicly_accessible = true
    }
    two = {
      identifier     = "static-member-1"
      instance_class = "db.r5.2xlarge"
    }
    three = {
      identifier     = "excluded-member-1"
      instance_class = "db.r5.large"
      promotion_tier = 15
    }
  }

5. Create heterogenous cluster to support mixed-use workloads w/ autoscaling enabled

• Resources created:
  • Writer: 1
  • Reader(s):
    • At least 3 readers (2 created directly, 1 created through appautoscaling)
    • At most 7 readers (2 created directly, 5 created through appautoscaling)

ℹ️ Autoscaling uses the instance class specified by instance_class.

  instance_class = "db.r5.large"
  instances = {
    one = {
      instance_class      = "db.r5.2xlarge"
      publicly_accessible = true
    }
    two = {
      identifier     = "static-member-1"
      instance_class = "db.r5.2xlarge"
    }
    three = {
      identifier     = "excluded-member-1"
      instance_class = "db.r5.large"
      promotion_tier = 15
    }
  }

  autoscaling_enabled      = true
  autoscaling_min_capacity = 1
  autoscaling_max_capacity = 5

Conditional Creation

The following values are provided to toggle on/off creation of the associated resources as desired:

# This RDS cluster will not be created
module "cluster" {
  source  = "terraform-aws-modules/rds-aurora/aws"

  # Disable creation of cluster and all resources
  create = false

  # Disable creation of subnet group - provide a subnet group
  create_db_subnet_group = false

  # Disable creation of security group - provide a security group
  create_security_group = false

  # Disable creation of monitoring IAM role - provide a role ARN
  create_monitoring_role = false

  # ... omitted
}

Examples

• Autoscaling: A PostgreSQL cluster with enhanced monitoring and autoscaling enabled
• Global Cluster: A PostgreSQL global cluster with clusters provisioned in two different region
• Multi-AZ: A multi-AZ RDS cluster (not using Aurora engine)
• MySQL: A simple MySQL cluster
• PostgreSQL: A simple PostgreSQL cluster
• S3 Import: A MySQL cluster created from a Percona Xtrabackup stored in S3
• Serverless: Serverless V1 and V2 (PostgreSQL and MySQL)

Documentation

Terraform documentation is generated automatically using pre-commit hooks. Follow installation instructions here.

Requirements

Name	Version
terraform	>= 1.0
aws	>= 5.64

Providers

Name	Version
aws	>= 5.64

Modules

No modules.

Resources

Name	Type
aws_appautoscaling_policy.this	resource
aws_appautoscaling_target.this	resource
aws_cloudwatch_log_group.this	resource
aws_db_parameter_group.this	resource
aws_db_subnet_group.this	resource
aws_iam_role.rds_enhanced_monitoring	resource
aws_iam_role_policy_attachment.rds_enhanced_monitoring	resource
aws_rds_cluster.this	resource
aws_rds_cluster_activity_stream.this	resource
aws_rds_cluster_endpoint.this	resource
aws_rds_cluster_instance.this	resource
aws_rds_cluster_parameter_group.this	resource
aws_rds_cluster_role_association.this	resource
aws_secretsmanager_secret_rotation.this	resource
aws_security_group.this	resource
aws_security_group_rule.this	resource
aws_iam_policy_document.monitoring_rds_assume_role	data source
aws_partition.current	data source

Inputs

Name	Description	Type	Default	Required
allocated_storage	The amount of storage in gibibytes (GiB) to allocate to each DB instance in the Multi-AZ DB cluster. (This setting is required to create a Multi-AZ DB cluster)	number	null	no
allow_major_version_upgrade	Enable to allow major engine version upgrades when changing engine versions. Defaults to false	bool	false	no
apply_immediately	Specifies whether any cluster modifications are applied immediately, or during the next maintenance window. Default is false	bool	null	no
auto_minor_version_upgrade	Indicates that minor engine upgrades will be applied automatically to the DB instance during the maintenance window. Default true	bool	null	no
autoscaling_enabled	Determines whether autoscaling of the cluster read replicas is enabled	bool	false	no
autoscaling_max_capacity	Maximum number of read replicas permitted when autoscaling is enabled	number	2	no
autoscaling_min_capacity	Minimum number of read replicas permitted when autoscaling is enabled	number	0	no
autoscaling_policy_name	Autoscaling policy name	string	"target-metric"	no
autoscaling_scale_in_cooldown	Cooldown in seconds before allowing further scaling operations after a scale in	number	300	no
autoscaling_scale_out_cooldown	Cooldown in seconds before allowing further scaling operations after a scale out	number	300	no
autoscaling_target_connections	Average number of connections threshold which will initiate autoscaling. Default value is 70% of db.r4/r5/r6g.large's default max_connections	number	700	no
autoscaling_target_cpu	CPU threshold which will initiate autoscaling	number	70	no
availability_zones	List of EC2 Availability Zones for the DB cluster storage where DB cluster instances can be created. RDS automatically assigns 3 AZs if less than 3 AZs are configured, which will show as a difference requiring resource recreation next Terraform apply	list(string)	null	no
backtrack_window	The target backtrack window, in seconds. Only available for aurora engine currently. To disable backtracking, set this value to 0. Must be between 0 and 259200 (72 hours)	number	null	no
backup_retention_period	The days to retain backups for	number	null	no
ca_cert_identifier	The identifier of the CA certificate for the DB instance	string	null	no
cloudwatch_log_group_class	Specified the log class of the log group. Possible values are: STANDARD or INFREQUENT_ACCESS	string	null	no
cloudwatch_log_group_kms_key_id	The ARN of the KMS Key to use when encrypting log data	string	null	no
cloudwatch_log_group_retention_in_days	The number of days to retain CloudWatch logs for the DB instance	number	7	no
cloudwatch_log_group_skip_destroy	Set to true if you do not wish the log group (and any logs it may contain) to be deleted at destroy time, and instead just remove the log group from the Terraform state	bool	null	no
cluster_ca_cert_identifier	The CA certificate identifier to use for the DB cluster's server certificate. Currently only supported for multi-az DB clusters	string	null	no
cluster_members	List of RDS Instances that are a part of this cluster	list(string)	null	no
cluster_performance_insights_enabled	Valid only for Non-Aurora Multi-AZ DB Clusters. Enables Performance Insights for the RDS Cluster	bool	null	no
cluster_performance_insights_kms_key_id	Valid only for Non-Aurora Multi-AZ DB Clusters. Specifies the KMS Key ID to encrypt Performance Insights data. If not specified, the default RDS KMS key will be used (aws/rds)	string	null	no
cluster_performance_insights_retention_period	Valid only for Non-Aurora Multi-AZ DB Clusters. Specifies the amount of time to retain performance insights data for. Defaults to 7 days if Performance Insights are enabled. Valid values are 7, month * 31 (where month is a number of months from 1-23), and 731	number	null	no
cluster_tags	A map of tags to add to only the cluster. Used for AWS Instance Scheduler tagging	map(string)	{}	no
cluster_timeouts	Create, update, and delete timeout configurations for the cluster	map(string)	{}	no
cluster_use_name_prefix	Whether to use name as a prefix for the cluster	bool	false	no
copy_tags_to_snapshot	Copy all Cluster tags to snapshots	bool	null	no
create	Whether cluster should be created (affects nearly all resources)	bool	true	no
create_cloudwatch_log_group	Determines whether a CloudWatch log group is created for each enabled_cloudwatch_logs_exports	bool	false	no
create_db_cluster_activity_stream	Determines whether a cluster activity stream is created.	bool	false	no
create_db_cluster_parameter_group	Determines whether a cluster parameter should be created or use existing	bool	false	no
create_db_parameter_group	Determines whether a DB parameter should be created or use existing	bool	false	no
create_db_subnet_group	Determines whether to create the database subnet group or use existing	bool	false	no
create_monitoring_role	Determines whether to create the IAM role for RDS enhanced monitoring	bool	true	no
create_security_group	Determines whether to create security group for RDS cluster	bool	true	no
database_name	Name for an automatically created database on cluster creation	string	null	no
db_cluster_activity_stream_kms_key_id	The AWS KMS key identifier for encrypting messages in the database activity stream	string	null	no
db_cluster_activity_stream_mode	Specifies the mode of the database activity stream. Database events such as a change or access generate an activity stream event. One of: sync, async	string	null	no
db_cluster_db_instance_parameter_group_name	Instance parameter group to associate with all instances of the DB cluster. The db_cluster_db_instance_parameter_group_name is only valid in combination with allow_major_version_upgrade	string	null	no
db_cluster_instance_class	The compute and memory capacity of each DB instance in the Multi-AZ DB cluster, for example db.m6g.xlarge. Not all DB instance classes are available in all AWS Regions, or for all database engines	string	null	no
db_cluster_parameter_group_description	The description of the DB cluster parameter group. Defaults to "Managed by Terraform"	string	null	no
db_cluster_parameter_group_family	The family of the DB cluster parameter group	string	""	no
db_cluster_parameter_group_name	The name of the DB cluster parameter group	string	null	no
db_cluster_parameter_group_parameters	A list of DB cluster parameters to apply. Note that parameters may differ from a family to an other	list(map(string))	[]	no
db_cluster_parameter_group_use_name_prefix	Determines whether the DB cluster parameter group name is used as a prefix	bool	true	no
db_parameter_group_description	The description of the DB parameter group. Defaults to "Managed by Terraform"	string	null	no
db_parameter_group_family	The family of the DB parameter group	string	""	no
db_parameter_group_name	The name of the DB parameter group	string	null	no
db_parameter_group_parameters	A list of DB parameters to apply. Note that parameters may differ from a family to an other	list(map(string))	[]	no
db_parameter_group_use_name_prefix	Determines whether the DB parameter group name is used as a prefix	bool	true	no
db_subnet_group_name	The name of the subnet group name (existing or created)	string	""	no
delete_automated_backups	Specifies whether to remove automated backups immediately after the DB cluster is deleted	bool	null	no
deletion_protection	If the DB instance should have deletion protection enabled. The database can't be deleted when this value is set to true. The default is false	bool	null	no
domain	The ID of the Directory Service Active Directory domain to create the instance in	string	null	no
domain_iam_role_name	(Required if domain is provided) The name of the IAM role to be used when making API calls to the Directory Service	string	null	no
enable_global_write_forwarding	Whether cluster should forward writes to an associated global cluster. Applied to secondary clusters to enable them to forward writes to an aws_rds_global_cluster's primary cluster	bool	null	no
enable_http_endpoint	Enable HTTP endpoint (data API). Only valid when engine_mode is set to serverless	bool	null	no
enable_local_write_forwarding	Whether read replicas can forward write operations to the writer DB instance in the DB cluster. By default, write operations aren't allowed on reader DB instances.	bool	null	no
enabled_cloudwatch_logs_exports	Set of log types to export to cloudwatch. If omitted, no logs will be exported. The following log types are supported: audit, error, general, slowquery, postgresql	list(string)	[]	no
endpoints	Map of additional cluster endpoints and their attributes to be created	any	{}	no
engine	The name of the database engine to be used for this DB cluster. Defaults to aurora. Valid Values: aurora, aurora-mysql, aurora-postgresql	string	null	no
engine_lifecycle_support	The life cycle type for this DB instance. This setting is valid for cluster types Aurora DB clusters and Multi-AZ DB clusters. Valid values are open-source-rds-extended-support, open-source-rds-extended-support-disabled. Default value is open-source-rds-extended-support.	string	null	no
engine_mode	The database engine mode. Valid values: global, multimaster, parallelquery, provisioned, serverless. Defaults to: provisioned	string	"provisioned"	no
engine_native_audit_fields_included	Specifies whether the database activity stream includes engine-native audit fields. This option only applies to an Oracle DB instance. By default, no engine-native audit fields are included	bool	false	no
engine_version	The database engine version. Updating this argument results in an outage	string	null	no
final_snapshot_identifier	The name of your final DB snapshot when this DB cluster is deleted. If omitted, no final snapshot will be made	string	null	no
global_cluster_identifier	The global cluster identifier specified on aws_rds_global_cluster	string	null	no
iam_database_authentication_enabled	Specifies whether or mappings of AWS Identity and Access Management (IAM) accounts to database accounts is enabled	bool	null	no
iam_role_description	Description of the monitoring role	string	null	no
iam_role_force_detach_policies	Whether to force detaching any policies the monitoring role has before destroying it	bool	null	no
iam_role_managed_policy_arns	Set of exclusive IAM managed policy ARNs to attach to the monitoring role	list(string)	null	no
iam_role_max_session_duration	Maximum session duration (in seconds) that you want to set for the monitoring role	number	null	no
iam_role_name	Friendly name of the monitoring role	string	null	no
iam_role_path	Path for the monitoring role	string	null	no
iam_role_permissions_boundary	The ARN of the policy that is used to set the permissions boundary for the monitoring role	string	null	no
iam_role_use_name_prefix	Determines whether to use iam_role_name as is or create a unique name beginning with the iam_role_name as the prefix	bool	false	no
iam_roles	Map of IAM roles and supported feature names to associate with the cluster	map(map(string))	{}	no
instance_class	Instance type to use at master instance. Note: if autoscaling_enabled is true, this will be the same instance class used on instances created by autoscaling	string	""	no
instance_timeouts	Create, update, and delete timeout configurations for the cluster instance(s)	map(string)	{}	no
instances	Map of cluster instances and any specific/overriding attributes to be created	any	{}	no
instances_use_identifier_prefix	Determines whether cluster instance identifiers are used as prefixes	bool	false	no
iops	The amount of Provisioned IOPS (input/output operations per second) to be initially allocated for each DB instance in the Multi-AZ DB cluster	number	null	no
is_primary_cluster	Determines whether cluster is primary cluster with writer instance (set to false for global cluster and replica clusters)	bool	true	no
kms_key_id	The ARN for the KMS encryption key. When specifying kms_key_id, storage_encrypted needs to be set to true	string	null	no
manage_master_user_password	Set to true to allow RDS to manage the master user password in Secrets Manager. Cannot be set if master_password is provided	bool	true	no
manage_master_user_password_rotation	Whether to manage the master user password rotation. Setting this value to false after previously having been set to true will disable automatic rotation.	bool	false	no
master_password	Password for the master DB user. Note that this may show up in logs, and it will be stored in the state file. Required unless manage_master_user_password is set to true or unless snapshot_identifier or replication_source_identifier is provided or unless a global_cluster_identifier is provided when the cluster is the secondary cluster of a global database	string	null	no
master_user_password_rotate_immediately	Specifies whether to rotate the secret immediately or wait until the next scheduled rotation window.	bool	null	no
master_user_password_rotation_automatically_after_days	Specifies the number of days between automatic scheduled rotations of the secret. Either master_user_password_rotation_automatically_after_days or master_user_password_rotation_schedule_expression must be specified	number	null	no
master_user_password_rotation_duration	The length of the rotation window in hours. For example, 3h for a three hour window.	string	null	no
master_user_password_rotation_schedule_expression	A cron() or rate() expression that defines the schedule for rotating your secret. Either master_user_password_rotation_automatically_after_days or master_user_password_rotation_schedule_expression must be specified	string	null	no
master_user_secret_kms_key_id	The Amazon Web Services KMS key identifier is the key ARN, key ID, alias ARN, or alias name for the KMS key	string	null	no
master_username	Username for the master DB user. Required unless snapshot_identifier or replication_source_identifier is provided or unless a global_cluster_identifier is provided when the cluster is the secondary cluster of a global database	string	null	no
monitoring_interval	The interval, in seconds, between points when Enhanced Monitoring metrics are collected for instances. Set to 0 to disable. Default is 0	number	0	no
monitoring_role_arn	IAM role used by RDS to send enhanced monitoring metrics to CloudWatch	string	""	no
name	Name used across resources created	string	""	no
network_type	The type of network stack to use (IPV4 or DUAL)	string	null	no
performance_insights_enabled	Specifies whether Performance Insights is enabled or not	bool	null	no
performance_insights_kms_key_id	The ARN for the KMS key to encrypt Performance Insights data	string	null	no
performance_insights_retention_period	Amount of time in days to retain Performance Insights data. Either 7 (7 days) or 731 (2 years)	number	null	no
port	The port on which the DB accepts connections	string	null	no
predefined_metric_type	The metric type to scale on. Valid values are RDSReaderAverageCPUUtilization and RDSReaderAverageDatabaseConnections	string	"RDSReaderAverageCPUUtilization"	no
preferred_backup_window	The daily time range during which automated backups are created if automated backups are enabled using the backup_retention_period parameter. Time in UTC	string	"02:00-03:00"	no
preferred_maintenance_window	The weekly time range during which system maintenance can occur, in (UTC)	string	"sun:05:00-sun:06:00"	no
publicly_accessible	Determines whether instances are publicly accessible. Default false	bool	null	no
putin_khuylo	Do you agree that Putin doesn't respect Ukrainian sovereignty and territorial integrity? More info: https://en.wikipedia.org/wiki/Putin_khuylo!	bool	true	no
replication_source_identifier	ARN of a source DB cluster or DB instance if this DB cluster is to be created as a Read Replica	string	null	no
restore_to_point_in_time	Map of nested attributes for cloning Aurora cluster	map(string)	{}	no
s3_import	Configuration map used to restore from a Percona Xtrabackup in S3 (only MySQL is supported)	map(string)	{}	no
scaling_configuration	Map of nested attributes with scaling properties. Only valid when engine_mode is set to serverless	map(string)	{}	no
security_group_description	The description of the security group. If value is set to empty string it will contain cluster name in the description	string	null	no
security_group_name	The security group name. Default value is (var.name)	string	""	no
security_group_rules	Map of security group rules to add to the cluster security group created	any	{}	no
security_group_tags	Additional tags for the security group	map(string)	{}	no
security_group_use_name_prefix	Determines whether the security group name (var.name) is used as a prefix	bool	true	no
serverlessv2_scaling_configuration	Map of nested attributes with serverless v2 scaling properties. Only valid when engine_mode is set to provisioned	map(string)	{}	no
skip_final_snapshot	Determines whether a final snapshot is created before the cluster is deleted. If true is specified, no snapshot is created	bool	false	no
snapshot_identifier	Specifies whether or not to create this cluster from a snapshot. You can use either the name or ARN when specifying a DB cluster snapshot, or the ARN when specifying a DB snapshot	string	null	no
source_region	The source region for an encrypted replica DB cluster	string	null	no
storage_encrypted	Specifies whether the DB cluster is encrypted. The default is true	bool	true	no
storage_type	Determines the storage type for the DB cluster. Optional for Single-AZ, required for Multi-AZ DB clusters. Valid values for Single-AZ: aurora, "" (default, both refer to Aurora Standard), aurora-iopt1 (Aurora I/O Optimized). Valid values for Multi-AZ: io1 (default).	string	null	no
subnets	List of subnet IDs used by database subnet group created	list(string)	[]	no
tags	A map of tags to add to all resources	map(string)	{}	no
vpc_id	ID of the VPC where to create security group	string	""	no
vpc_security_group_ids	List of VPC security groups to associate to the cluster in addition to the security group created	list(string)	[]	no

Outputs

Name	Description
additional_cluster_endpoints	A map of additional cluster endpoints and their attributes
cluster_arn	Amazon Resource Name (ARN) of cluster
cluster_ca_certificate_identifier	CA identifier of the CA certificate used for the DB instance's server certificate
cluster_ca_certificate_valid_till	Expiration date of the DB instance’s server certificate
cluster_database_name	Name for an automatically created database on cluster creation
cluster_endpoint	Writer endpoint for the cluster
cluster_engine_version_actual	The running version of the cluster database
cluster_hosted_zone_id	The Route53 Hosted Zone ID of the endpoint
cluster_id	The RDS Cluster Identifier
cluster_instances	A map of cluster instances and their attributes
cluster_master_password	The database master password
cluster_master_user_secret	The generated database master user secret when manage_master_user_password is set to true
cluster_master_username	The database master username
cluster_members	List of RDS Instances that are a part of this cluster
cluster_port	The database port
cluster_reader_endpoint	A read-only endpoint for the cluster, automatically load-balanced across replicas
cluster_resource_id	The RDS Cluster Resource ID
cluster_role_associations	A map of IAM roles associated with the cluster and their attributes
db_cluster_activity_stream_kinesis_stream_name	The name of the Amazon Kinesis data stream to be used for the database activity stream
db_cluster_cloudwatch_log_groups	Map of CloudWatch log groups created and their attributes
db_cluster_parameter_group_arn	The ARN of the DB cluster parameter group created
db_cluster_parameter_group_id	The ID of the DB cluster parameter group created
db_cluster_secretsmanager_secret_rotation_enabled	Specifies whether automatic rotation is enabled for the secret
db_parameter_group_arn	The ARN of the DB parameter group created
db_parameter_group_id	The ID of the DB parameter group created
db_subnet_group_name	The db subnet group name
enhanced_monitoring_iam_role_arn	The Amazon Resource Name (ARN) specifying the enhanced monitoring role
enhanced_monitoring_iam_role_name	The name of the enhanced monitoring role
enhanced_monitoring_iam_role_unique_id	Stable and unique string identifying the enhanced monitoring role
security_group_id	The security group ID of the cluster

Authors

Module is maintained by Anton Babenko with help from these awesome contributors.

License

Apache 2 Licensed. See LICENSE for full details.

Additional information for users from Russia and Belarus

• Russia has illegally annexed Crimea in 2014 and brought the war in Donbas followed by full-scale invasion of Ukraine in 2022.
• Russia has brought sorrow and devastations to millions of Ukrainians, killed hundreds of innocent people, damaged thousands of buildings, and forced several million people to flee.
• Putin khuylo!