Working with directory buckets

Directory buckets organize data hierarchically into directories as opposed to the flat storage structure of general purpose buckets. There aren't prefix limits for directory buckets, and individual directories can scale horizontally.

You can create up to 100 directory buckets in each of your AWS accounts, with no limit on the number of objects that you can store in a bucket. Your bucket quota is applied to each Region in your AWS account. If your application requires increasing this limit, contact Support.

There are several types of Amazon S3 buckets. Before creating a bucket, make sure that you choose the bucket type that best fits your application and performance requirements. For more information about the various bucket types and the appropriate use cases for each, see Buckets.

The following topics provide information about directory buckets. For more information about general purpose buckets, see General purpose buckets overview.

For more information about directory buckets, see the following topics.

Directory bucket names

A directory bucket name consists of a base name that you provide and a suffix that contains the ID of the Zone (Availability Zone or Local Zone) that your bucket is located in. Directory bucket names must use the following format and follow the naming rules for directory buckets:

bucket-base-name--zone-id--x-s3

For example, the following directory bucket name contains the Availability Zone ID usw2-az1:

bucket-base-name--usw2-az1--x-s3

For more information, see Directory bucket naming rules.

Directories

Directory buckets organize data hierarchically into directories as opposed to the flat sorting structure of general purpose buckets.

With a hierarchical namespace, the delimiter in the object key is important. The only supported delimiter is a forward slash (/). Directories are determined by delimiter boundaries. For example, the object key dir1/dir2/file1.txt results in the directories dir1/ and dir2/ being automatically created, and the object file1.txt being added to the /dir2 directory in the path dir1/dir2/file1.txt.

The directory bucket indexing model returns unsorted results for the ListObjectsV2 API operation. If you need to limit your results to a subsection of your bucket, you can specify a subdirectory path in the prefix parameter, for example, prefix=dir1/.

Key names

For directory buckets, subdirectories that are common to multiple object keys are created with the first object key. Additional object keys for the same subdirectory use the previously created subdirectory. This model gives you flexibility in choosing object keys that are best suited to the application, with equal support for sparse and dense directories.

Access management

Directory buckets have all S3 Block Public Access settings enabled by default at the bucket level. S3 Object Ownership is set to bucket owner enforced and access control lists (ACLs) are disabled. These settings can't be modified.

By default, users don't have permissions for directory buckets. To grant access permissions for directory buckets, you can use IAM to create users, groups, or roles and attach permissions to those identities. For more information, see Authorizing Regional endpoint API operations with IAM.

You can also control access to directory buckets through access points. Access points simplify managing data access at scale for shared datasets in Amazon S3. Access points are unique hostnames you create to enforce distinct permissions and network controls for all requests made through an access point. For more information, see Managing access to shared datasets in directory buckets with access points.

Directory buckets quotas

Quotas, also referred to as limits, are the maximum number of service resources or operations for your AWS account. The following are the quotas for directory buckets. For more information on quotas in Amazon S3, see Amazon S3 quotas.

Creating and using directory buckets

For more information about working with directory buckets, see the following topics.