How to set "ec2 auto recovery" action on EC2 instance?

[Pankajc123]

❓ General Issue

The Question

How can I set "ec2 auto recovery" action on EC2 instance, using "Alarm" construct?

Environment

• CDK CLI Version: 1.21.1
• Module Version:
• OS: Windows
• Language: .Net

Other information

I can create an Alarm using code snippet below

var ec2recoveryalarm = new Alarm(this, "EC2InstanceRecoveryAlarm", new AlarmProps{
                AlarmName = "Sample",
                AlarmDescription = "Trigger a recovery when instance status check fails for 5 consecutive minutes.",
                ComparisonOperator = ComparisonOperator.GREATER_THAN_THRESHOLD,
                Statistic = "Minimum",
                Period = Duration.Seconds(60),
                EvaluationPeriods = 5,
                Threshold = 0,
                Metric = new Metric(new MetricProps{
                    MetricName = "StatusCheckFailed_System",
                    Namespace = "AWS/EC2",
                    Dimensions = new Dictionary<string, object>()
                    {
                        {"InstanceId", primaryec2instance.InstanceId}
                    }
                }),
                ActionsEnabled = true                
            });   

I am not sure how to add ec2 auto recovery action on same alarm.

I tried something like this but didn't work.

  ec2recoveryalarm.AddAlarmAction(new[]{(IAlarmAction) new  AlarmActionConfig{
             AlarmActionArn = Fn.Sub("arn:${AWS::Partition}:automate:${AWS::Region}:ec2:recover")
   }});

I am trying to add following resource in my CF template

"EC2InstanceRecoveryAlarm" : {
            "Type" : "AWS::CloudWatch::Alarm",
            "Properties" : {
                "AlarmDescription" : "Trigger a recovery when instance status check fails for 5 consecutive minutes.",
                "MetricName" : "StatusCheckFailed_System",
                "Namespace" : "AWS/EC2",
                "Statistic" : "Minimum",
                "Period" : "60",
                "EvaluationPeriods" : "5",
                "Threshold" : "0",
                "ComparisonOperator" : "GreaterThanThreshold",
                "AlarmActions" : [ {"Fn::Join" : ["", ["arn:", {"Ref" : "AWS::Partition"}, ":automate:", { "Ref" : "AWS::Region" }, ":ec2:recover" ]]} ],
                "Dimensions" : [ {
                    "Name" : "InstanceId",
                    "Value" : {"Ref" : "AllInOneEC2Instance"}
                } ]
            }
        }

I can add all properties except "AlarmActions" as mentioned above using "Alarm" construct.

I can add all properties including "AlarmActions" with "CfnAlarm" construct. But I want to achieve same using "Alarm" construct.

"CfnAlarm" construct code snippet is as below.

var ec2recoveryalarm = new CfnAlarm(this, "PrimaryInstanceRecoveryAlarm", new CfnAlarmProps{
                AlarmDescription = "Trigger a recovery when instance status check fails for 5 consecutive minutes.",
                MetricName = "StatusCheckFailed_System",
                Namespace = "AWS/EC2",
                Statistic = "Minimum",
                Period = 60,
                EvaluationPeriods = 5,
                Threshold = 0,
                ComparisonOperator = "GreaterThanThreshold",
                AlarmActions = new[]{Fn.Sub("arn:${AWS::Partition}:automate:${AWS::Region}:ec2:recover")},
                Dimensions = new[]{new CfnAlarm.DimensionProperty{
                    Name = "InstanceId",
                    Value = primaryec2instance.Ref
                }}
            }); 

Any help in this regards is much appreciated.

[rix0rrr]

We're happy to help you out, but GitHub issues is not a support forum. There are
websites much better suited for that, such as StackOverflow.

Please ask that same question again on StackOverflow under the
aws-cdk. If you can't get
a response to your question, please bring it to our attention again and we will
do our best to answer it.

[IndikaUdagedara]

You can do something like this

1. Implement IAlarmAction

export class Ec2Action implements IAlarmAction {
  actionArn: string;
  constructor(actionArn: string) {
    this.actionArn = actionArn;
  }

  bind(
    scope: cdk.Construct,
    alarm: cloudwatch.IAlarm
  ): cloudwatch.AlarmActionConfig {
    return { alarmActionArn: this.actionArn };
  }
}

2. Use it like this

    statusCheckAlarm.addAlarmAction(
      new Ec2Action(`arn:aws:automate:${region}:ec2:recover`)
    );

A full example below

    const statusCheckMetric = new cloudwatch.Metric({
      metricName: "StatusCheckFailed_System",
      namespace: "AWS/EC2",
      dimensions: {
        InstanceId: <instanceId>
      },
      statistic: "Minimum",
      period: cdk.Duration.minutes(1),
    });

    const statusCheckAlarm = statusCheckMetric.createAlarm(
      this,
      `StatusCheckAlarm`,
      {
        evaluationPeriods: 5,
        threshold: 0,
        comparisonOperator:
          cloudwatch.ComparisonOperator.GREATER_THAN_THRESHOLD,
        statistic: "Minimum",
      }
    );

    statusCheckAlarm.addAlarmAction(
      new SnsAction(props.alarmTopic),
      new Ec2Action(`arn:aws:automate:${props.env?.region}:ec2:recover`)
    );