---
layout: default
navsection: installguide
title: Configure S3 object storage
...
{% comment %}
Copyright (C) The Arvados Authors. All rights reserved.

SPDX-License-Identifier: CC-BY-SA-3.0
{% endcomment %}

Keepstore can store data in object storage compatible with the S3 API, such as Amazon S3, Google Cloud Storage, Ceph RADOS, NetApp StorageGRID, and others.

Volumes are configured in the @Volumes@ section of the cluster configuration file.

# "Configuration example":#example
# "IAM Policy":#IAM

h2(#example). Configuration example

{% include 'assign_volume_uuid' %}

<notextile><pre><code>    Volumes:
      <span class="userinput">ClusterID</span>-nyw5e-<span class="userinput">000000000000000</span>:
        AccessViaHosts:
          # This section determines which keepstore servers access the
          # volume. In this example, keep0 has read/write access, and
          # keep1 has read-only access.
          #
          # If the AccessViaHosts section is empty or omitted, all
          # keepstore servers will have read/write access to the
          # volume.
          "http://<span class="userinput">keep0.ClusterID.example.com</span>:25107": {}
          "http://<span class="userinput">keep1.ClusterID.example.com</span>:25107": {ReadOnly: true}

        Driver: <span class="userinput">S3</span>
        DriverParameters:
          # Bucket name.
          Bucket: <span class="userinput">example-bucket-name</span>

          # Optionally, you can specify S3 access credentials here.
          # If these are left blank, IAM role credentials will be
          # retrieved from instance metadata (IMDSv2).
          AccessKeyID: <span class="userinput">""</span>
          SecretAccessKey: <span class="userinput">""</span>

          # Storage provider region. If Endpoint is specified, the
          # region determines the request signing method, and defaults
          # to "us-east-1".
          Region: <span class="userinput">us-east-1</span>

          # Storage provider endpoint. For Amazon S3, use "" or
          # omit. For Google Cloud Storage, use
          # "https://storage.googleapis.com".
          Endpoint: ""

          # Change to true if the region requires a LocationConstraint
          # declaration.
          LocationConstraint: false

          # Use V2 signatures instead of the default V4. Amazon S3
          # supports V4 signatures in all regions, but this option
          # might be needed for other S3-compatible services.
          V2Signature: false

          # By default keepstore stores data using the MD5 checksum
          # (32 hexadecimal characters) as the object name, e.g.,
          # "0123456abc...". Setting PrefixLength to 3 changes this
          # naming scheme to "012/0123456abc...". This can improve
          # performance, depending on the S3 service being used. For
          # example, PrefixLength 3 is recommended to avoid AWS
          # limitations on the number of read/write operations per
          # second per prefix (see
          # https://aws.amazon.com/premiumsupport/knowledge-center/s3-request-limit-avoid-throttling/).
          #
          # Note that changing PrefixLength on an existing volume is
          # not currently supported. Once you have started using a
          # bucket as an Arvados volume, you should not change its
          # configured PrefixLength, or configure another volume using
          # the same bucket and a different PrefixLength.
          PrefixLength: 0

          # Requested page size for "list bucket contents" requests.
          IndexPageSize: 1000

          # Maximum time to wait while making the initial connection
          # to the backend before failing the request.
          ConnectTimeout: 1m

          # Maximum time to wait for a complete response from the
          # backend before failing the request.
          ReadTimeout: 2m

          # Maximum eventual consistency latency
          RaceWindow: 24h

        # How much replication is provided by the underlying bucket.
        # This is used to inform replication decisions at the Keep
        # layer.
        Replication: 2

        # If true, do not accept write or trash operations, even if
        # AccessViaHosts.*.ReadOnly is false.
        #
        # If false or omitted, enable write access (subject to
        # AccessViaHosts.*.ReadOnly, where applicable).
        ReadOnly: false

        # Storage classes to associate with this volume.  See "Storage
        # classes" in the "Admin" section of doc.arvados.org.
        StorageClasses: null
</code></pre></notextile>

h2(#IAM). IAM Policy

On Amazon, VMs which will access the S3 bucket (these include keepstore and compute nodes) will need an IAM policy with "permission that can read, write, list and delete objects in the bucket":https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_create.html .  Here is an example policy:

<notextile>
<pre>
{
    "Id": "arvados-keepstore policy",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                  "s3:*"
            ],
            "Resource": "arn:aws:s3:::xarv1-nyw5e-000000000000000-volume"
            "Resource": "arn:aws:s3:::xarv1-nyw5e-000000000000000-volume/*"
        }
    ]
}
</pre>
</notextile>