Managing S3 on Outposts capacity with Amazon CloudWatch metrics

To help manage the fixed S3 capacity on your Outpost, we recommend that you create CloudWatch alerts that tell you when your storage utilization exceeds a certain threshold. For more information about the CloudWatch metrics for S3 on Outposts, see CloudWatch metrics. If there is not enough space to store an object on your Outpost, the API returns an insufficient capacity exemption (ICE). To free up space, you can create CloudWatch alarms that trigger explicit data deletion, or use a lifecycle expiration policy to expire objects. To save data before deletion, you can use AWS DataSync to copy data from your Amazon S3 on Outposts bucket to an S3 bucket in an AWS Region. For more information about using DataSync, see Getting Started with AWS DataSync in the AWS DataSync User Guide.

CloudWatch metrics

The S3Outposts namespace includes the following metrics for Amazon S3 on Outposts buckets. You can monitor the total number of S3 on Outposts bytes provisioned, the total free bytes available for objects, and the total size of all objects for a given bucket. Bucket or account-related metrics exist for all direct S3 usage. Indirect S3 usage, such as storing Amazon Elastic Block Store local snapshots or Amazon Relational Database Service backups on an Outpost, consumes S3 capacity, but is not included in bucket or account-related metrics. For more information about Amazon EBS local snapshots, see Amazon EBS local snapshots on Outposts. To see your Amazon EBS cost report, visit https://console.aws.amazon.com/billing/.

Note

S3 on Outposts supports only the following metrics, and no other Amazon S3 metrics.

Because S3 on Outposts has a fixed capacity limit, we recommend creating CloudWatch alarms to notify you when your storage utilization exceeds a certain threshold.

Metric	Description	Time Period	Units	Type
OutpostTotalBytes	The total provisioned capacity in bytes for an Outpost.	5 minutes	Bytes	S3 on Outposts
OutpostFreeBytes	The count of free bytes available on an Outpost to store customer data.	5 minutes	Bytes	S3 on Outposts
BucketUsedBytes	The total size of all objects for the given bucket.	5 minutes	Bytes	S3 on Outposts. Direct S3 usage only.
AccountUsedBytes	The total size of all objects for the specified Outposts account.	5 minutes	Bytes	S3 on Outposts. Direct S3 usage only.
BytesPendingReplication	The total number of bytes of objects that are pending replication for a given replication rule. For more information about how to enable replication metrics, see Creating replication rules between Outposts.	5 minutes	Bytes	Optional. For S3 Replication on Outposts.
OperationsPendingReplication	The total number of operations that are pending replication for a given replication rule. For more information about how to enable replication metrics, see Creating replication rules between Outposts.	5 minutes	Counts	Optional. For S3 Replication on Outposts.
ReplicationLatency	The current number of seconds delay by which the replication destination bucket is behind the source bucket for a given replication rule. For more information about how to enable replication metrics, see Creating replication rules between Outposts.	5 minutes	Seconds	Optional. For S3 Replication on Outposts.