Terraform resource: aws cloudwatch metric alarm

• https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/cloudwatch_metric_alarm
• aws_cloudwatch_metric_alarm

• actions_enabled = "true" (optional)

Official example

resource "aws_cloudwatch_metric_alarm" "nlb_healthyhosts" {
 alarm_name          = "alarmname"
 comparison_operator = "LessThanThreshold"
 evaluation_periods  = "1"
 metric_name         = "HealthyHostCount"
 namespace           = "AWS/NetworkELB"
 period              = "60"
 statistic           = "Average"
 threshold           = var.logstash_servers_count
 alarm_description   = "Number of healthy nodes in Target Group"
 actions_enabled     = "true"
 alarm_actions       = [aws_sns_topic.sns.arn]
 ok_actions          = [aws_sns_topic.sns.arn]
 dimensions = {
   TargetGroup  = aws_lb_target_group.lb-tg.arn_suffix
   LoadBalancer = aws_lb.lb.arn_suffix
 }
}

Examples

LB

resource "aws_cloudwatch_metric_alarm" "lb_targets_not_available" {
 alarm_name          = format("%s-%s", lower("${var.rds_name}"), "db-highCPUUtilization")
 comparison_operator = "LessThanOrEqualToThreshold"
 evaluation_periods  = "2"
 metric_name         = "CPUUtilization"
 namespace           = "AWS/NetworkELB"
 period              = "30"
 statistic           = "SampleCount"
 threshold           = "0"
 alarm_description   = "No healthy target group available to LB listener"

 dimensions = {
   HealthyHostCount = aws_lb.your-load-balancer-name.id
 }
}

AWS/RDS

CPU

resource "aws_cloudwatch_metric_alarm" "db_cpu_utilization_too_high" {
 alarm_name          = format("%s-%s", lower("${var.rds_name}"), "db-highCPUUtilization")
 comparison_operator = "GreaterThanThreshold"
 evaluation_periods  = "5"
 metric_name         = "CPUUtilization"
 namespace           = "AWS/RDS"
 period              = "120"
 statistic           = "Average"
 threshold           = "80"
 alarm_description   = "Average database CPU utilization is too high."

 dimensions = {
   DBInstanceIdentifier = aws_db_instance.rds_instance.id
 }
}

DiskQueueDepth

resource "aws_cloudwatch_metric_alarm" "db_disk_queue_depth_too_high" {
 alarm_name          = format("%s-%s", lower("${var.rds_name}"), "db-highDiskQueueDepth")
 comparison_operator = "GreaterThanThreshold"
 evaluation_periods  = "2"
 metric_name         = "DiskQueueDepth"
 namespace           = "AWS/RDS"
 period              = "120"
 statistic           = "Average"
 threshold           = "10"
 alarm_description   = "Average database disk queue depth is too high, performance may be negatively impacted."

 dimensions = {
   DBInstanceIdentifier = aws_db_instance.rds_instance.id
 }
}

FreeStorageSpace

resource "aws_cloudwatch_metric_alarm" "db_disk_free_storage_space_too_low" {
 alarm_name          = format("%s-%s", lower("${var.rds_name}"), "db-lowFreeStorageSpace")
 comparison_operator = "LessThanThreshold"
 evaluation_periods  = "2"
 metric_name         = "FreeStorageSpace"
 namespace           = "AWS/RDS"
 period              = "120"
 statistic           = "Average"
 threshold           = "10"
 alarm_description   = "Average database free storage space is too low and may fill up soon."

 dimensions = {
   DBInstanceIdentifier = aws_db_instance.rds_instance.id
 }
}

FreeableMemory

resource "aws_cloudwatch_metric_alarm" "db_memory_freeable_too_low" {
 alarm_name          = format("%s-%s", lower("${var.rds_name}"), "db-lowFreeableMemory")
 comparison_operator = "LessThanThreshold"
 evaluation_periods  = "2"
 metric_name         = "FreeableMemory"
 namespace           = "AWS/RDS"
 period              = "120"
 statistic           = "Average"
 threshold           = "10"
 alarm_description   = "Average database freeable memory is too low, performance may be negatively impacted."

 dimensions = {
   DBInstanceIdentifier = aws_db_instance.rds_instance.id
 }
}

ChatGPT examples for ALB (01/2023)

resource "aws_cloudwatch_metric_alarm" "elb_5xx_error_rate" {
 alarm_name                = "elb_5xx_error_rate"
 comparison_operator       = "GreaterThanThreshold"
 evaluation_periods        = "5"
 metric_name               = "HTTPCode_Backend_5XX"
 namespace                 = "AWS/ApplicationELB"
 period                    = "60"
 statistic                 = "SampleCount"
 threshold                 = "1"
 alarm_description         = "This alarm will notify when the 5XX error rate is greater than 1% for 5 consecutive minutes"
 alarm_actions             = [aws_sns_topic.example.arn]
 dimensions = {
   LoadBalancer = aws_elbv2_load_balancer.example.name
 }
}

resource "aws_cloudwatch_metric_alarm" "elb_response_time" {
 alarm_name                = "elb_response_time"
 comparison_operator       = "GreaterThanThreshold"
 evaluation_periods        = "5"
 metric_name               = "TargetResponseTime"
 namespace                 = "AWS/ApplicationELB"
 period                    = "60"
 statistic                 = "Average"
 threshold                 = "2"
 alarm_description         = "This alarm will notify when the average response time is greater than 2 seconds for 5 consecutive data points"
 alarm_actions             = [aws_sns_topic.example.arn]
 dimensions = {
   LoadBalancer = aws_elbv2_load_balancer.example.name
 }
}

resource "aws_cloudwatch_metric_alarm" "elb_response_time" {
 alarm_name                = "elb_response_time"
 comparison_operator       = "GreaterThanThreshold"
 evaluation_periods        = "5"
 metric_name               = "TargetResponseTime"
 namespace                 = "AWS/ApplicationELB"
 period                    = "60"
 statistic                 = "Maximum"
 threshold                 = "1"
 alarm_description         = "This alarm will notify when the maximum response time is greater than 1 second for 5 consecutive data points"
 alarm_actions             = [aws_sns_topic.example.arn]
 dimensions = {
   LoadBalancer = aws_elbv2_load_balancer.example.name
 }
}

resource "aws_cloudwatch_metric_alarm" "elb_response_time_90th_percentile" {
 alarm_name                = "elb_response_time_90th_percentile"
 comparison_operator       = "GreaterThanThreshold"
 evaluation_periods        = "5"
 metric_name               = "TargetResponseTime"
 namespace                 = "AWS/ApplicationELB"
 period                    = "60"
 statistic                 = "p90"
 threshold                 = "1"
 alarm_description         = "This alarm will notify when the 90th percentile of the response time is greater than 1 second for 5 consecutive data points"
 alarm_actions             = [aws_sns_topic.example.arn]
 dimensions = {
   LoadBalancer = aws_elbv2_load_balancer.example.name
 }
}

resource "aws_sns_topic" "example" {
 name = "example-topic"
}

Related

• aws cloudwatch metric alarm
• alarm_actions
• aws_sns_topic

See also

• Terraform AWS CloudWatch: aws_cloudwatch_metric_alarm, aws_cloudwatch_log_group, aws_cloudwatch_dashboard
• Terraform AWS: provider, resources, modules, data sources, VPC, IAM, Net, EC2, S3, Route53, ACM, CloudWatch, SES, RDS, ECS, awscc, autoscaling, EKS