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Data Storage Modules 0.40.1Last updated in version 0.38.1

RDS Proxy Module

View Source Release Notes

Amazon RDS Proxy is a fully managed database proxy service that makes it easy to manage database connections for Amazon Relational Database Service (RDS) and Amazon Aurora. It allows you to efficiently pool and share database connections among multiple application processes, reducing the connection overhead on your database instances and providing improved scalability, availability, and security for your database workloads.

RDS Proxy works by creating a secure database proxy endpoint that applications can connect to instead of connecting directly to the database instance. When an application connects to the proxy endpoint, the proxy establishes and manages the database connections on behalf of the application, pooling connections and multiplexing requests to reduce overhead and improve performance. It also provides features like connection pooling, read/write splitting, and automatic failover to improve database availability and resilience.

How to use the RDS Proxy Module

In order to setup a RDS proxy, you need to setup database credentials in AWS Secrets Manager and pass it to this module. Refer to the examples/rds-proxy or https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/rds-proxy-setup.html#rds-proxy-secrets-arns for more information.

If you use a customer managed KMS key to encrypt the secret, you will need to provide the KMS key ARN to this module using the db_secret_kms_key_arn parameter.

Setting up a RDS proxy requires the following steps, which is handled by this module:

  • Setting up network prerequisites
  • Setting up database credentials
  • Setting up AWS Identity and Access Management (IAM) policies

Configuring access to RDS Proxy

If you don't provide the allow_connections_from_cidr_blocks variable, you will need to provision your own access. To do that create an ingress rule on the security group that this module creates. The security group ID will be available from the security_group_id output variable.

Testing the connection to RDS Proxy

You connect to an RDS DB instance through a proxy in generally the same way as you connect directly to the database. The main difference is that you specify the proxy endpoint instead of the DB endpoint. When using this module, the proxy endpoint will be avaialable from the rds_proxy_endpoint output variable. Note that RDS Proxy can't be publicly accessible, so you might need to use provision EC2 instance inside the same VPC to test the connection.

Sample Usage

main.tf

# ------------------------------------------------------------------------------------------------------
# DEPLOY GRUNTWORK'S RDS-PROXY MODULE
# ------------------------------------------------------------------------------------------------------

module "rds_proxy" {

source = "git::git@github.com:gruntwork-io/terraform-aws-data-storage.git//modules/rds-proxy?ref=v0.40.1"

# ----------------------------------------------------------------------------------------------------
# REQUIRED VARIABLES
# ----------------------------------------------------------------------------------------------------

# The number of seconds that a connection to the proxy can be inactive before
# the proxy disconnects it. You can set this value higher or lower than the
# connection timeout limit for the associated database.
connection_pool_config = <object(
connection_borrow_timeout = number
init_query = string
max_connections_percent = number
max_idle_connections_percent = number
session_pinning_filters = list(string)
)>

# The DB secret should contain username and password for the DB as a key-value
# pairs. Otherwise, you can insert plaintext secret with the format should
# look like {"username":"your_username","password":"your_password"}.
db_secret_arn = <string>

# The kinds of databases that the proxy can connect to. This value determines
# which database network protocol the proxy recognizes when it interprets
# network traffic to and from the database. The engine family applies to MySQL
# and PostgreSQL for both RDS and Aurora. Valid values are MYSQL and
# POSTGRESQL.
engine_family = <string>

# The identifier for the proxy.
name = <string>

# A list of subnet ids where the database instances should be deployed. In the
# standard Gruntwork VPC setup, these should be the private persistence subnet
# ids. This is ignored if create_subnet_group=false.
subnet_ids = <list(string)>

# The id of the VPC in which this DB should be deployed.
vpc_id = <string>

# ----------------------------------------------------------------------------------------------------
# OPTIONAL VARIABLES
# ----------------------------------------------------------------------------------------------------

# A list of CIDR-formatted IP address ranges that can connect to this DB.
# Should typically be the CIDR blocks of the private app subnet in this VPC
# plus the private subnet in the mgmt VPC.
allow_connections_from_cidr_blocks = []

# Configuration block(s) with authorization mechanisms to connect to the
# associated instances or clusters
auth = {}

# The DB cluster identifier. Note that one of `db_instance_identifier` or
# `db_cluster_identifier` is required.
db_cluster_identifier = null

# The DB instance identifier. Note that one of `db_instance_identifier` or
# `db_cluster_identifier` is required.
db_instance_identifier = null

# The KMS key used to encrypt the DB secret.
db_secret_kms_key_arn = null

# The number of seconds that a connection to the proxy can be inactive before
# the proxy disconnects it. You can set this value higher or lower than the
# connection timeout limit for the associated database.
idle_client_timeout = null

# The port the RDS proxy will listen on (e.g. 3306)
port = 3306

# The number of seconds that a connection to the proxy can be inactive before
# the proxy disconnects it. You can set this value higher or lower than the
# connection timeout limit for the associated database.
require_tls = null

}


Reference

Required

connection_pool_configobject(…)required

The number of seconds that a connection to the proxy can be inactive before the proxy disconnects it. You can set this value higher or lower than the connection timeout limit for the associated database.

object({
connection_borrow_timeout = number
init_query = string
max_connections_percent = number
max_idle_connections_percent = number
session_pinning_filters = list(string)
})
db_secret_arnstringrequired

The DB secret should contain username and password for the DB as a key-value pairs. Otherwise, you can insert plaintext secret with the format should look like {'username':'your_username','password':'your_password'}.

engine_familystringrequired

The kinds of databases that the proxy can connect to. This value determines which database network protocol the proxy recognizes when it interprets network traffic to and from the database. The engine family applies to MySQL and PostgreSQL for both RDS and Aurora. Valid values are MYSQL and POSTGRESQL.

namestringrequired

The identifier for the proxy.

subnet_idslist(string)required

A list of subnet ids where the database instances should be deployed. In the standard Gruntwork VPC setup, these should be the private persistence subnet ids. This is ignored if create_subnet_group=false.

vpc_idstringrequired

The id of the VPC in which this DB should be deployed.

Optional

A list of CIDR-formatted IP address ranges that can connect to this DB. Should typically be the CIDR blocks of the private app subnet in this VPC plus the private subnet in the mgmt VPC.

[]
authmap(object(…))optional

Configuration block(s) with authorization mechanisms to connect to the associated instances or clusters

map(object({
auth_scheme = optional(string, "SECRETS")
secret_arn = string
description = optional(string)
iam_auth = optional(string, "DISABLED") # REQUIRED or DISABLED
client_password_auth_type = optional(string)
}))
{}
db_cluster_identifierstringoptional

The DB cluster identifier. Note that one of db_instance_identifier or db_cluster_identifier is required.

null

The DB instance identifier. Note that one of db_instance_identifier or db_cluster_identifier is required.

null
db_secret_kms_key_arnstringoptional

The KMS key used to encrypt the DB secret.

null
idle_client_timeoutnumberoptional

The number of seconds that a connection to the proxy can be inactive before the proxy disconnects it. You can set this value higher or lower than the connection timeout limit for the associated database.

null
portnumberoptional

The port the RDS proxy will listen on (e.g. 3306)

3306
require_tlsbooloptional

The number of seconds that a connection to the proxy can be inactive before the proxy disconnects it. You can set this value higher or lower than the connection timeout limit for the associated database.

null