Rule: Lambda functions should be configured with a dead-letter queue

Rule Description

Troubleshooting Steps

2. 1.

   Check Lambda Configuration: Verify that the dead-letter queue configuration is indeed missing in the Lambda function.

4. 2.

   Review CloudWatch Logs: Check the CloudWatch Logs for the Lambda function to see if any error messages or exceptions are being logged.

6. 3.

   Investigate Function Role Permissions: Ensure that the IAM role associated with the Lambda function has the necessary permissions to write to the dead-letter queue. Check for any permission-related errors in the function's execution log.

8. 4.

   Examine Queue Permissions: Validate the permissions of the dead-letter queue to confirm that Lambda has the necessary write permissions to the queue.

10. 5.

    Test Function Invocation: Invoke the Lambda function and monitor the response. If the function fails, ensure that the error is not due to a missing dead-letter queue.

Code Configuration

Using AWS Management Console:

2. 1.

   Open the AWS Management Console and navigate to the AWS Lambda service.

4. 2.

   Select the Lambda function for which you want to configure the dead-letter queue.

6. 3.

   Under the Configuration tab, scroll down to the Dead Letter Queue section and click "Edit".

8. 4.

   Choose an existing SQS (Simple Queue Service) queue or create a new one.

10. 5.

    Click "Save" to apply the changes.

Using AWS CLI:

2. 1.

   Open your preferred command-line interface.

4. 2.

   Use the

   aws lambda update-function-configuration

   command, specifying the function name and the

   --dead-letter-config

   parameter with the ARN (Amazon Resource Name) of the desired dead-letter queue.

aws lambda update-function-configuration \
--function-name <function-name> \
--dead-letter-config TargetArn=<dead-letter-queue-arn>

2. 1.
   Execute the command and verify the successful update of the Lambda function's configuration.

Remediation Steps

2. 1.

   Identify the Lambda functions for which a dead-letter queue needs to be configured.

4. 2.

   Choose the appropriate method (AWS Management Console or AWS CLI) to configure the dead-letter queue as mentioned in the previous section.

6. 3.

   If using the AWS Management Console:

   • Navigate to the Lambda service in the AWS Management Console.
   • Select the Lambda function that requires a dead-letter queue.
   • Under the Configuration tab, locate the Dead Letter Queue section.
   • Click "Edit" and select an existing SQS queue or create a new one.
   • Click "Save" to apply the changes.
8. 4.

   If using the AWS CLI:

   • Open your preferred command-line interface.
   • Use the

     aws lambda update-function-configuration

     command as specified in the previous section.
   • Replace

     <function-name>

     and

     <dead-letter-queue-arn>

     with the appropriate values.
   • Execute the command to update the Lambda function's configuration.
10. 5.

    Verify that the dead-letter queue configuration is successful by checking the Lambda function's details or using the AWS CLI.

12. 6.

    Retest the Lambda function to ensure that any failed invocations are sent to the configured dead-letter queue for error handling and troubleshooting purposes.