Terraform Module for AWS RDS Cloudwatch Alarms

This Terraform module manages Cloudwatch Alarms for an RDS instance. It does NOT create or manage RDS, only Metric Alarms.

Requires:

• AWS Provider
• Terraform 0.13 or higher

If you need Terraform 0.12, you should use version 2.x of this module and contribute changes to the tf-0.12 branch.

Alarms Created

Alarms Always Created (default values can be overridden):

• CPU Utilization above 90%
• Disk queue depth above 64
• Disk space less than 10 GB
• EBS Volume burst balance less than 100
• Freeable memory below 256 MB
• Swap usage above 256 MB
• Anomalous connection count

If the instance type is a T-Series instance type (automatically determind), the following alarms are also created:

• CPU Credit Balance below 100

If the database engine is any of postgres type (configured with var.engine), then the following alarms are also created:

• Maximum used transaction IDs over 1,000,000,000 [reference]

Estimated Operating Cost: $ 1.00 / month

• $ 0.10 / month for Metric Alarms (7x)
• $ 0.30 / month for Anomaly Alarm (1x)

Example

resource "aws_db_instance" "default" {
  allocated_storage    = 10
  storage_type         = "gp2"
  engine               = "mysql"
  engine_version       = "5.7"
  instance_class       = "db.t2.micro"
  identifier_prefix    = "rds-server-example"
  db_name               = "my-db"
  username             = "foo"
  password             = "bar"
  parameter_group_name = "default.mysql5.7"
  apply_immediately    = "true"
  skip_final_snapshot  = "true"
}

resource "aws_sns_topic" "default" {
  name_prefix = "my-premade-topic"
}

module "aws-rds-alarms" {
  source            = "lorenzoaiello/rds-alarms/aws"
  version           = "x.y.z"
  db_instance_id    = aws_db_instance.default.identifier
  db_instance_class = "db.t2.micro"
  actions_alarm     = [aws_sns_topic.default.arn]
  actions_ok        = [aws_sns_topic.default.arn]
}

This above can pair very nicely for example with an module which creates an SNS topic which sends your alerts into Slack. For example:

resource "aws_db_instance" "default" {
  allocated_storage    = 10
  storage_type         = "gp2"
  engine               = "mysql"
  engine_version       = "5.7"
  instance_class       = "db.t2.micro"
  identifier_prefix    = "rds-server-example"
  db_name              = "my-db"
  username             = "foo"
  password             = "bar"
  parameter_group_name = "default.mysql5.7"
  apply_immediately    = "true"
  skip_final_snapshot  = "true"
}

module "notify_slack" {
  source  = "terraform-aws-modules/notify-slack/aws"
  version = "~> 4.0"

  sns_topic_name = "slack-topic"

  slack_webhook_url = "https://hooks.slack.com/services/AAA/BBB/CCC"
  slack_channel     = "aws-notification"
  slack_username    = "reporter"
}

module "aws-rds-alarms" {
  source            = "lorenzoaiello/rds-alarms/aws"
  version           = "x.y.z"
  db_instance_id    = aws_db_instance.default.identifier
  db_instance_class = "db.t2.micro"
  actions_alarm     = [module.sns_to_slack.this_slack_topic_arn]
  actions_ok        = [module.sns_to_slack.this_slack_topic_arn]
}

Variables

Outputs