Final answer:
To troubleshoot AWS Lambda function failures, examine CloudWatch Logs for errors, check the function's permissions, adjust timeout settings and memory allocation if necessary, and manually invoke the function to test its execution.
Step-by-step explanation:
To troubleshoot failures in an AWS Lambda function, start by reviewing the logs that are generated by the function. Lambda automatically integrates with Amazon CloudWatch Logs to record all the requests made to your function and to store the output of each. To view the logs, open the Amazon CloudWatch console, and locate the log group and stream associated with your Lambda function. Look for error messages or stack traces that can provide insights into what went wrong.
Next, ensure that your Lambda function has the necessary permissions set up in its execution role. The execution role should allow your function to access other AWS services it needs. If permissions are misconfigured, your function may fail silently.
Another common issue could be a timeout. By default, the maximum runtime is set to 3 seconds. If your function requires more time to complete, increase the timeout setting in the configuration settings of your Lambda function.
Also, check the amount of memory allocated to your function. Insufficient memory can cause your function to run out of memory and fail. Adjust the memory allocation in the function's configuration if needed.
Lastly, use the AWS Lambda console to manually invoke your function with a test event to see if the function runs as expected. This can help you identify if there is an issue with the event triggering your function or with the function code itself.