ELB Other 5XX Alarm

What is

AWS CDK construct library for a CloudWatch Alarm for Elastic Load Balancing that fires on HTTPCode_ELB_5XX_Count excluding 500, 502, 503, and 504 (e.g. 501, 505, 561).

Metrics for concrete status codes such as 500 are provided (e.g. HTTPCode_ELB_500_Count). Therefore, it is useful to distinguish detection from them.

For more information, please see the following blog page. here.

CloudWatch Composite Alarm

The "ELB Other 5XX Alarm" by this construct uses the CloudWatch Composite Alarm.

The alarm rule for this composite alarm is as follows.

ALARM(HTTPCode_ELB_5XX_Count)
AND (
    NOT (
        ALARM(HTTPCode_ELB_500_Count)
        OR ALARM(HTTPCode_ELB_502_Count)
        OR ALARM(HTTPCode_ELB_503_Count)
        OR ALARM(HTTPCode_ELB_504_Count)
    )
)

This is actually implemented using a suppressor alarm.

Usage

npm install elb-other-5xx-alarm

import { ELBOther5XXAlarm } from 'elb-other-5xx-alarm';

new ELBOther5XXAlarm(this, 'ELBOther5XXAlarm', {
  alarmName: 'my-alarm',
  alarmActions: alarmActions, // e.g. [new SnsAction(new Topic(this, 'Topic', {}))]
  loadBalancerFullName: alb.loadBalancerFullName, // e.g. 'app/alb/123456789'
  period: Duration.seconds(60),
  threshold: 1,
  evaluationPeriods: 1,
});