Working with Amazon S3 Buckets
Amazon S3 is cloud storage for the Internet. To upload your data (photos, videos, documents etc.), you first create a bucket in one of the AWS regions. You can then upload any number of objects to the bucket.
In terms of implementation, buckets and objects are resources, and Amazon S3 provides APIs for you to manage them. For example, you can create a bucket and upload objects using the Amazon S3 API. You can also use the Amazon S3 console to perform these operations. The console internally uses the Amazon S3 APIs to send requests to Amazon S3.
In this section, we explain working with buckets. For information about working with objects, see Working with Amazon S3 Objects.
Amazon S3 bucket names are globally unique, regardless of the AWS region in which you create the bucket. You specify the name at the time you create the bucket. For bucket naming guidelines, see Bucket Restrictions and Limitations.
Amazon S3 creates bucket in a region you specify. You can choose any AWS region that is geographically close to you to optimize latency, minimize costs, or address regulatory requirements. For example, if you reside in Europe, you might find it advantageous to create buckets in the EU (Ireland) or EU (Frankfurt) regions. For a list of AWS Amazon S3 regions, go to Regions and Endpoints in the AWS General Reference.
Objects belonging to a bucket that you create in a specific AWS region never leave that region, unless you explicitly transfer them to another region. For example, objects stored in the EU (Ireland) region never leave it.
Creating a Bucket
Amazon S3 provides APIs for you to create and manage buckets. By default, you can create up to 100 buckets in each of your AWS accounts. If you need additional buckets, you can increase your bucket limit by submitting a service limit increase. To learn more about submitting a bucket limit increase, go to AWS Service Limits in the AWS General Reference.
When you create a bucket, you provide a name and AWS region where you want the bucket created. The next section (see Accessing a Bucket) discusses DNS-compliant bucket names.
Within each bucket, you can store any number of objects. You can create a bucket using any of the following methods:
Create the bucket using the console.
Create the bucket programmatically using the AWS SDKs.
If you need to, you can also make the Amazon S3 REST API calls directly from your code. However, this can be cumbersome because it requires you to write code to authenticate your requests. For more information, go to PUT Bucket in the Amazon Simple Storage Service API Reference.
When using AWS SDKs you first create a client and then send a request to create a bucket using the client. You can specify an AWS region when you create the client ( US East (N. Virginia) is the default region). You can also specify a region in your create bucket request. Note the following:
If you create a client by specifying the US East (N. Virginia) region, it uses the following endpoint to communicate with Amazon S3.
You can use this client to create a bucket in any AWS region. In your create bucket request,
If you don’t specify a region, Amazon S3 creates the bucket in the US East (N. Virginia) region.
If you specify an AWS region, Amazon S3 creates the bucket in the specified region.
If you create a client by specifying any other AWS region, each of these regions maps to the region-specific endpoint:
For example, if you create a client by specifying the eu-west-1 region, it maps to the following region-specific endpoint:
In this case, you can use the client to create a bucket only in the eu-west-1 region. Amazon S3 returns an error if you specify any other region in your create bucket request.
For a list of available AWS regions, go to Regions and Endpoints in the AWS General Reference.
For examples, see Examples of Creating a Bucket.
You can use your AWS account root credentials to create a bucket and perform any other Amazon S3 operation. However, AWS recommends not using the root credentials of your AWS account to make requests such as create a bucket. Instead, create an IAM user, and grant that user full access (users by default have no permissions). We refer to these users as administrator users. You can use the administrator user credentials, instead of the root credentials of your account, to interact with AWS and perform tasks, such as create a bucket, create users, and grant them permissions.
The AWS account that creates a resource owns that resource. For example, if you create an IAM user in your AWS account and grant the user permission to create a bucket, the user can create a bucket. But the user does not own the bucket; the AWS account to which the user belongs owns the bucket. The user will need additional permission from the resource owner to perform any other bucket operations. For more information about managing permissions for your Amazon S3 resources, see Managing Access Permissions to Your Amazon S3 Resources.
Accessing a Bucket
You can access your bucket using the Amazon S3 console. Using the console UI, you can perform almost all bucket operations without having to write any code.
If you access a bucket programmatically, note that Amazon S3 supports RESTful architecture in which your buckets and objects are resources, each with a resource URI that uniquely identify the resource.
Amazon S3 supports both virtual-hosted–style and path-style URLs to access a bucket.
In a virtual-hosted–style URL, the bucket name is part of the domain name in the URL. For example:
In a virtual-hosted–style URL, you can use either of these endpoints. If you make a request to the
http://endpoint, the DNS has sufficient information to route your request directly to the region where your bucket resides.
In a path-style URL, the bucket name is not part of the domain (unless you use a region-specific endpoint). For example:
US East (N. Virginia) region endpoint,
In a path-style URL, the endpoint you use must match the region in which the bucket resides. For example, if your bucket is in the South America (São Paulo) region, you must use the
http://s3-sa-east-1.amazonaws.com/bucketendpoint. If your bucket is in the US East (N. Virginia) region, you must use the
Because buckets can be accessed using path-style and virtual-hosted–style URLs, we recommend you create buckets with DNS-compliant bucket names. For more information, see Bucket Restrictions and Limitations.
For more information, see Virtual Hosting of Buckets.
Bucket Configuration Options
Amazon S3 supports various options for you to configure your bucket. For example, you can configure your bucket for website hosting, add configuration to manage lifecycle of objects in the bucket, and configure the bucket to log all access to the bucket. Amazon S3 supports subresources for you to store, and manage the bucket configuration information. That is, using the Amazon S3 API, you can create and manage these subresources. You can also use the console or the AWS SDKs.
There are also object-level configurations. For example, you can configure object-level permissions by configuring an access control list (ACL) specific to that object.
These are referred to as subresources because they exist in the context of a specific bucket or object. The following table lists subresources that enable you to manage bucket-specific configurations.
You can define lifecycle rules for objects in your bucket that have a well-defined lifecycle. For example, you can define a rule to archive objects one year after creation, or delete an object 10 years after creation.
For more information, see Object Lifecycle Management.
You can configure your bucket for static website hosting. Amazon S3 stores this configuration by creating a website subresource.
For more information, see Hosting a Static Website on Amazon S3.
Versioning helps you recover accidental overwrites and deletes.
We recommend versioning as a best practice to recover objects from being deleted or overwritten by mistake.
For more information, see Using Versioning.
policy and ACL (Access Control List)
All your resources (such as buckets and objects) are private by default. Amazon S3 supports both bucket policy and access control list (ACL) options for you to grant and manage bucket-level permissions. Amazon S3 stores the permission information in the policy and acl subresources.
For more information, see Managing Access Permissions to Your Amazon S3 Resources.
cors (cross-origin resource sharing)
You can configure your bucket to allow cross-origin requests.
For more information, see Enabling Cross-Origin Resource Sharing.
Logging enables you to track requests for access to your bucket. Each access log record provides details about a single access request, such as the requester, bucket name, request time, request action, response status, and error code, if any. Access log information can be useful in security and access audits. It can also help you learn about your customer base and understand your Amazon S3 bill.
For more information, see Server Access Logging.
You can add cost allocation tags to your bucket to categorize and track your AWS costs. Amazon S3 provides the tagging subresource to store and manage tags on a bucket. Using tags you apply to your bucket, AWS generates a cost allocation report with usage and costs aggregated by your tags.
For more information, see Billing and Reporting of Buckets.
When you create a bucket, you specify the AWS region where you want Amazon S3 to create the bucket. Amazon S3 stores this information in the location subresource and provides an API for you to retrieve this information.
You can enable your bucket to send you notifications of specified bucket events.
For more information, see Configuring Amazon S3 Event Notifications.
Amazon S3 stores object version information in this subresource.
By default, the AWS account that creates the bucket (the bucket owner) pays for downloads from the bucket. Using this subresource, the bucket owner can specify that the person requesting the download will be charged for the download. Amazon S3 provides an API for you to manage this subresource.
For more information, see Requester Pays Buckets.