---
layout: docs
page_title: S3 - Storage Backends - Configuration
description: |-
  The S3 storage backend is used to persist Vault's data in an Amazon S3
  bucket.
---

# S3 storage backend

The S3 storage backend is used to persist Vault's data in an [Amazon S3][s3]
bucket.

- **No High Availability** – the S3 storage backend does not support high
  availability.

- **Community Supported** – the S3 storage backend is supported by the
  community. While it has undergone review by HashiCorp employees, they may not
  be as knowledgeable about the technology. If you encounter problems with them,
  you may be referred to the original author.

```hcl
storage "s3" {
  access_key = "abcd1234"
  secret_key = "defg5678"
  bucket     = "my-bucket"
}
```

## `s3` parameters

- `bucket` `(string: <required>)` – Specifies the name of the S3 bucket. This
  can also be provided via the environment variable `AWS_S3_BUCKET`.

- `endpoint` `(string: "")` – Specifies an alternative, AWS compatible, S3
  endpoint. This can also be provided via the environment variable
  `AWS_S3_ENDPOINT`.

- `region` `(string "us-east-1")` – Specifies the AWS region. This can also be
  provided via the environment variable `AWS_REGION` or `AWS_DEFAULT_REGION`,
  in that order of preference.

The following settings are used for authenticating to AWS. If you are
running your Vault server on an EC2 instance, you can also make use of the EC2
instance profile service to provide the credentials Vault will use to make
S3 API calls. Leaving the `access_key` and `secret_key` fields empty will
cause Vault to attempt to retrieve credentials from the AWS metadata service.

- `access_key` – Specifies the AWS access key. This can also be provided via
  the environment variable `AWS_ACCESS_KEY_ID`, AWS credential files, or by
  IAM role.

- `secret_key` – Specifies the AWS secret key. This can also be provided via
  the environment variable `AWS_SECRET_ACCESS_KEY`, AWS credential files, or
  by IAM role.

- `session_token` `(string: "")` – Specifies the AWS session token. This can
  also be provided via the environment variable `AWS_SESSION_TOKEN`.

- `max_parallel` `(string: "128")` – Specifies the maximum number of concurrent
  requests to S3.

- `s3_force_path_style` `(string: "false")` - Specifies whether to use host
  bucket style domains with the configured endpoint.

- `disable_ssl` `(string: "false")` - Specifies if SSL should be used for the
  endpoint connection (highly recommended not to disable for production).

- `kms_key_id` `(string: "")` - Specifies the ID or Alias of the KMS key used to
  encrypt data in the S3 backend. Vault must have `kms:Encrypt`, `kms:Decrypt`
  and `kms:GenerateDataKey` permissions for this KMS key. You can use 
  `alias/aws/s3` to specify the default key for the account.

- `path` `(string: "")` - Specifies the path in the S3 Bucket where Vault
  data will be stored.

## `s3` examples

### Default example

This example shows using Amazon S3 as a storage backend.

```hcl
storage "s3" {
  access_key = "abcd1234"
  secret_key = "defg5678"
  bucket     = "my-bucket"
}
```

### S3 KMS encryption with default key

This example shows using Amazon S3 as a storage backend using KMS
encryption with the default S3 KMS key for the account.

```hcl
storage "s3" {
  access_key = "abcd1234"
  secret_key = "defg5678"
  bucket     = "my-bucket"
  kms_key_id = "alias/aws/s3"
}
```

### S3 KMS encryption with custom key

This example shows using Amazon S3 as a storage backend using KMS
encryption with a customer managed KMS key.

```hcl
storage "s3" {
  access_key = "abcd1234"
  secret_key = "defg5678"
  bucket     = "my-bucket"
  kms_key_id = "001234ac-72d3-9902-a3fc-0123456789ab"
}
```

[s3]: https://aws.amazon.com/s3/

## AWS instance metadata timeouts

@include 'aws-imds-timeout.mdx'
