Step 4: Configure a CloudWatch Alarm
To configure a CloudWatch alarm, follow the instructions at Create Alarm in the Amazon CloudWatch User Guide. As you follow the steps, note the following:
In Create Alarm (1. Select Metric step), choose Lambda Metrics, and then choose the Errors (Metric Name is Errors) for the Lambda function you created. Also, on the statistics drop-down, change the settings from Average to Sum statistics.
In Create Alarm (2. Define Metric step), set the alarm threshold to Whenever: Errors is >= 1 and select your Amazon SNS topic from the Send notification to: list.