AWS cloudwatch not triggering lambda function

amazon-cloudwatchamazon-lambdaamazon-web-services

I am trying to create a scheduling system for my EC2 instances using lambda functions to start/shutdown the instances and Cloudwatch to trigger and schedule them.
The problem is Cloudwatch, not triggering the lambda functions when the functions are working fine. I have linked Cloudwatch to the lambda function, and set it as the trigger. But Cloudwatch logs isn't showing any recollection of the instances changing state and the state of the instances don't change. Can anyone help?

Just to note: I have tested the lambda functions using the test feature, and they both work perfectly. I'm assuming the issue is with Cloudwatch.

Best Answer

It's probably a missing permission for CloudWatch to execute your Lambda. Have you got the CloudWatch Events Lambda triggers configured and enabled?

Have a look at this CloudFormation template that does exactly what you want - starts and stops a given Instance at specified times using CloudWatch Events Rule:

https://github.com/mludvig/ec2-start-stop

Hope that helps :)

Related Solutions

How to configure Cloudwatch events to trigger on IAM API calls

To monitor changes to IAM you will need to use a combination of CloudWatch, CloudWatch Logs and CloudTrail. Make sure that CloudTrail is enabled for each region that you wish to monitor.

CloudTrail will record calls to IAM and store in your CloudTrail logs. CloudTrail will publish events to CloudWatch logs. You setup a filter in CloudWatch to generate CloudWatch metrics from the CloudTrail events. These metrics are used to trigger alarms.

Your CloudWach filter looks like this:

{ ($.eventSource = "iam.amazonaws.com") }

This article will help you understand the process. Step-by-step with screenshots.

How to Receive Alerts When Your IAM Configuration Changes

Allow other AWS services to invoke Lambda using IAM

If I understood correctly. You are looking for IAM role to use in LambdaProxy integration. LambdaProxy does allow to use IAM role. Here is a snippet that I use:

Resources:
  APILambdaInvokeRole:
    Type: AWS::IAM::Role
    Properties:
      AssumeRolePolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Principal:
              Service:
                - "apigateway.amazonaws.com"
            Action:
              - "sts:AssumeRole"
  APILambdaInvokePolicy:
    Type: AWS::IAM::Policy
    Properties:
      PolicyName: LambdaInvokePolicy
      PolicyDocument:
        Version: 2012-10-17
        Statement:
          - Effect: Allow
            Action: "lambda:InvokeFunction"
            Resource: "*"
      Roles:
        - !Ref APILambdaInvokeRole

Best Answer

Related Solutions

How to configure Cloudwatch events to trigger on IAM API calls

Allow other AWS services to invoke Lambda using IAM

Related Topic