AWS Cloudwatch monitoring for S3

Question

Amazon Cloudwatch provides some very useful metrics for monitoring my EC2s, load balancers, elasticache and RDS databases, etc and allows me to set alarms for a whole range of criteria; but is there any way to configure it to monitor my S3s as well? Or are there any other monitoring tools (besides simply enabling logging) that will help me monitor the numbers of POST/GET requests and data volumes for my S3 resources? And to provide alarms for thresholds of activity or increased datastorage?

Answer 1

AWS S3 is a managed storage service. The only metrics available in AWS CloudWatch for S3 are NumberOfObjects and BucketSizeBytes . In order to understand your S3 usage better you need to do some extra work.

I have recently written an AWS Lambda function to do exactly what you ask for and it's available here:

https://github.com/maginetv/s3logs-cloudwatch

It works by parsing S3 Server side log files and aggregates/exports metrics to AWS Cloudwatch (CloudWatch allows you to publish custom metrics).

Example graphs that you will get in AWS CloudWatch after deploying this function on your AWS account are:

RestGetObject_RequestCount
RestPutObject_RequestCount
RestHeadObject_RequestCount
BatchDeleteObject_RequestCount
RestPostMultiObjectDelete_RequestCount
RestGetObject_HTTP_2XX_RequestCount
RestGetObject_HTTP_4XX_RequestCount
RestGetObject_HTTP_5XX_RequestCount
+ many others

Since metrics are exported to CloudWatch, you can easily set up alarms for them as well. CloudFormation template is included in GitHub repo and you can deploy this function very quickly to gain visibility into your S3 bucket usage.

EDIT 2016-12-10:

In November 2016 AWS has added extra S3 request metrics in CloudWatch that can be enabled when needed. This includes metrics like AllRequests , GetRequests , PutRequests , DeleteRequests , HeadRequests etc. See Monitoring Metrics with Amazon CloudWatch documentation for more details about this feature.

Answer 2

I was also unable to find any way to do this with CloudWatch. This question from April 2012 was answered by Derek@AWS as not having S3 support in CloudWatch. https://forums.aws.amazon.com/message.jspa?messageID=338089

The only thing I could think of would be to import the S3 access logs to a log service (like Splunk). Then create a custom cloud watch metric where you post the data that you parse from the logs. But then you have to filter out the polling of the access logs and… And while you were at it, you could just create the alarms in Splunk instead of in S3.

If your use case is to simply alert when you are using it too much, you could set up an account billing alert for your S3 usage.

Answer 3

I think this might depend on where you are looking to track the access from. Ie if you are trying to measure/watch usage of S3 objects from outside http/https requests then Anthony's suggestion if enabling S3 logging and then importing into splunk (or redshift) for analysis might work. You can also watch billing status on requests every day.

If trying to guage usage from within your own applications, there are some AWS SDK cloudwatch metrics:

http://docs.aws.amazon.com/AWSJavaSDK/latest/javadoc/com/amazonaws/metrics/package-summary.html

and

http://docs.aws.amazon.com/AWSJavaSDK/latest/javadoc/com/amazonaws/services/s3/metrics/S3ServiceMetric.html

Answer 4

S3 is a managed service, meaning that you don't need to take action based on system events in order to keep it up and running (as long as you can afford to pay for the service's usage). The spirit of CloudWatch is to help with monitoring services that require you to take action in order to keep them running.

For example, EC2 instances (which you manage yourself) typically need monitoring to alert when they're overloaded or when they're underused or else when they crash; at some point action needs to be taken in order to spin up new instances to scale out, spin down unused instances to scale back in, or reboot instances that have crashed. CloudWatch is meant to help you do the job of managing these resources more effectively.

Answer 5

To enable Request and Data transfer metrics in your bucket you can run the below command. Be aware that these are paid metrics.

aws s3api put-bucket-metrics-configuration \
    --bucket YOUR-BUCKET-NAME \
    --metrics-configuration Id=EntireBucket 
    --id EntireBucket 

This tutorial describes how to do it in AWS Console with point and click interface.