Terraform: Create New RDS instance & New Database in Existing RDS Instance

Create New RDS instance: Module

• https://registry.terraform.io/modules/terraform-aws-modules/rds/aws/latest

module "db" {
  source = "terraform-aws-modules/rds/aws"

  identifier = "demodb"

  engine            = "mysql"
  engine_version    = "5.7"
  instance_class    = "db.t3a.large"
  allocated_storage = 5

  db_name  = "demodb"
  username = "user"
  port     = "3306"

  iam_database_authentication_enabled = true

  vpc_security_group_ids = ["sg-12345678"]

  maintenance_window = "Mon:00:00-Mon:03:00"
  backup_window      = "03:00-06:00"

  # Enhanced Monitoring - see example for details on how to create the role
  # by yourself, in case you don't want to create it automatically
  monitoring_interval    = "30"
  monitoring_role_name   = "MyRDSMonitoringRole"
  create_monitoring_role = true

  tags = {
    Owner       = "user"
    Environment = "dev"
  }

  # DB subnet group
  create_db_subnet_group = true
  subnet_ids             = ["subnet-12345678", "subnet-87654321"]

  # DB parameter group
  family = "mysql5.7"

  # DB option group
  major_engine_version = "5.7"

  # Database Deletion Protection
  deletion_protection = true

  parameters = [
    {
      name  = "character_set_client"
      value = "utf8mb4"
    },
    {
      name  = "character_set_server"
      value = "utf8mb4"
    }
  ]

  options = [
    {
      option_name = "MARIADB_AUDIT_PLUGIN"

      option_settings = [
        {
          name  = "SERVER_AUDIT_EVENTS"
          value = "CONNECT"
        },
        {
          name  = "SERVER_AUDIT_FILE_ROTATIONS"
          value = "37"
        },
      ]
    },
  ]
}Code language: PHP (php)

New Database in Existing RDS Instance

If you want to create a database in an existing RDS instance, you can use the aws_rds_database resource instead of the rds_database module. The aws_rds_database resource allows you to specify the identifier of the existing RDS instance that you want to create the database in.

For example, the following Terraform configuration would create a database called my_database in the RDS instance with the identifier my_existing_rds_instance_identifier:

resource "aws_rds_database" "my_database" {
  db_instance_identifier = "my_existing_rds_instance_identifier"
  name = "my_database"
}Code language: JavaScript (javascript)

Rajesh Kumar

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