Multi-Region Access Point request routing - Amazon Simple Storage Service
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Multi-Region Access Point request routing

When you make a request through a Multi-Region Access Point, Amazon S3 determines which of the buckets that are associated with the Multi-Region Access Point can respond to its request with the lowest latency. Amazon S3 then directs the request to that bucket, regardless of the Amazon Region it is located in.

After the Multi-Region Access Point routes the request to the lowest-latency bucket, Amazon S3 processes the request as if you made it directly to that bucket. Multi-Region Access Points are not aware of the data contents of an Amazon S3 bucket. If you make GET requests to a Multi-Region Access Point, you can configure S3 Cross-Region Replication to create consistent datasets in your Amazon S3 buckets behind a Multi-Region Access Point. Then any bucket can fulfill the GET request successfully.

Amazon S3 directs Multi-Region Access Point requests according to the following rules:

  • Amazon S3 optimizes requests to be fulfilled with the lowest possible latency. It looks at the buckets supported by the Multi-Region Access Point and relays the request to the bucket that has the lowest latency.

  • If the request specifies an existing resource (for example, GetObject), Amazon S3 does not consider the name of the object when fulfilling the request. This means that an object might exist in one bucket in the Multi-Region Access Point, but your request will be routed to a bucket that does not contain the object. This will result in a 404 error message returned to the client. To ensure that your requests are fulfilled using the specific objects that you want, we recommend that you turn on bucket versioning and include version IDs in your requests. This helps ensure that you have the correct version of the object that you are looking for.

    We also recommend that you configure replication for your buckets. This helps resolve the potential issue when the object that you want is in a bucket in the Multi-Region Access Point, but it's not located in the specific bucket that your request was routed to. For more information about configuring replication, see Configuring bucket replication for use with Multi-Region Access Points.

  • If the request is to create a resource (for example, PutObject or CreateMultipartUpload), Amazon S3 fulfills the request using the lowest-latency bucket. For example, consider a video company that wants to support video uploads from anywhere in the world to the bucket with the lowest latency. When a user makes a PUT request to the Multi-Region Access Point;, the object is put into the bucket with the lowest latency. This demonstrates one of the reasons why bi-directional replication can be important. For more information about replication with Multi-Region Access Points, see Configuring bucket replication for use with Multi-Region Access Points