Changing the replica owner

To change replica ownership when source and destination buckets are owned by different AWS accounts (AWS CLI)

1. In this example, you create the source and destination buckets in two different AWS accounts. Configure the AWS CLI with two named profiles. This example uses profiles named acctA and acctB, respectively. For more information about setting credential profiles, see Named Profiles in the AWS Command Line Interface User Guide.

   Important

   The profiles you use for this exercise must have the necessary permissions. For example, in the replication configuration, you specify the IAM role that Amazon S3 can assume. You can do this only if the profile you use has the iam:PassRole permission. If you use administrator user credentials to create a named profile then you can perform all the tasks. For more information, see Granting a User Permissions to Pass a Role to an AWS Service in the IAM User Guide.

   You will need to make sure these profiles have necessary permissions. For example, the replication configuration includes an IAM role that Amazon S3 can assume. The named profile you use to attach such configuration to a bucket can do so only if it has the iam:PassRole permission. If you specify administrator user credentials when creating these named profiles, they have all the permissions. For more information, see Granting a User Permissions to Pass a Role to an AWS Service in the IAM User Guide.

2. Create the source bucket and enable versioning. This example creates the source bucket in the US East (N. Virginia) (us-east-1) Region.

   aws s3api create-bucket \
   --bucket source \
   --region us-east-1 \
   --profile acctA

   aws s3api put-bucket-versioning \
   --bucket source \
   --versioning-configuration Status=Enabled \
   --profile acctA

3. Create a destination bucket and enable versioning. This example creates the destination bucket in the US West (Oregon) (us-west-2) Region. Use an AWS account profile different from the one you used for the source bucket.

   aws s3api create-bucket \
   --bucket destination \
   --region us-west-2 \
   --create-bucket-configuration LocationConstraint=us-west-2 \
   --profile acctB

   aws s3api put-bucket-versioning \
   --bucket destination \
   --versioning-configuration Status=Enabled \
   --profile acctB

4. You must add permissions to your destination bucket policy to allow changing the replica ownership.

   1. Save the following policy to destination-bucket-policy.json.

      {
        "Version": "2012-10-17",
        "Statement": [
          {
            "Sid": "destination_bucket_policy_sid",
            "Principal": {
              "AWS": "source-bucket-owner-account-id"
            },
            "Action": [
              "s3:ReplicateObject",
              "s3:ReplicateDelete",
              "s3:ObjectOwnerOverrideToBucketOwner",
              "s3:ReplicateTags",
              "s3:GetObjectVersionTagging"
            ],
            "Effect": "Allow",
            "Resource": [
              "arn:aws:s3:::destination/*"
            ]
          }
        ]
      }                             
                                

   2. Put the above policy to destination bucket:

      aws s3api put-bucket-policy --region $ {destination_region} --bucket $ {destination} --policy file://destination_bucket_policy.json

5. Create an IAM role. You specify this role in the replication configuration that you add to the source bucket later. Amazon S3 assumes this role to replicate objects on your behalf. You create an IAM role in two steps:

   • Create a role.

   • Attach a permissions policy to the role.

   1. Create an IAM role.

      1. Copy the following trust policy and save it to a file named s3-role-trust-policy.json in the current directory on your local computer. This policy grants Amazon S3 permissions to assume the role.

         {
            "Version":"2012-10-17",
            "Statement":[
               {
                  "Effect":"Allow",
                  "Principal":{
                     "Service":"s3.amazonaws.com"
                  },
                  "Action":"sts:AssumeRole"
               }
            ]
         }

      2. Run the following AWS CLI command to create a role.

         $ aws iam create-role \
         --role-name replicationRole \
         --assume-role-policy-document file://s3-role-trust-policy.json  \
         --profile acctA

   2. Attach a permissions policy to the role.

      1. Copy the following permissions policy and save it to a file named s3-role-perm-pol-changeowner.json in the current directory on your local computer. This policy grants permissions for various Amazon S3 bucket and object actions. In the following steps, you create an IAM role and attach this policy to the role.

         {
            "Version":"2012-10-17",
            "Statement":[
               {
                  "Effect":"Allow",
                  "Action":[
                     "s3:GetObjectVersionForReplication",
                     "s3:GetObjectVersionAcl"
                  ],
                  "Resource":[
                     "arn:aws:s3:::source/*"
                  ]
               },
               {
                  "Effect":"Allow",
                  "Action":[
                     "s3:ListBucket",
                     "s3:GetReplicationConfiguration"
                  ],
                  "Resource":[
                     "arn:aws:s3:::source"
                  ]
               },
               {
                  "Effect":"Allow",
                  "Action":[
                     "s3:ReplicateObject",
                     "s3:ReplicateDelete",
                     "s3:ObjectOwnerOverrideToBucketOwner",
                     "s3:ReplicateTags",
                     "s3:GetObjectVersionTagging"
                  ],
                  "Resource":"arn:aws:s3:::destination/*"
               }
            ]
         }

      2. To create a policy and attach it to the role, run the following command.

         $ aws iam put-role-policy \
         --role-name replicationRole \
         --policy-document file://s3-role-perm-pol-changeowner.json \
         --policy-name replicationRolechangeownerPolicy \
         --profile acctA

6. Add a replication configuration to your source bucket.

   1. The AWS CLI requires specifying the replication configuration as JSON. Save the following JSON in a file named replication.json in the current directory on your local computer. In the configuration, the addition of AccessControlTranslation to indicate change in replica ownership.

      {
         "Role":"IAM-role-ARN",
         "Rules":[
            {
               "Status":"Enabled",
               "Priority":1,
               "DeleteMarkerReplication":{
                  "Status":"Disabled"
               },
               "Filter":{
               },
               "Status":"Enabled",
               "Destination":{
                  "Bucket":"arn:aws:s3:::destination",
                  "Account":"destination-bucket-owner-account-id",
                  "AccessControlTranslation":{
                     "Owner":"Destination"
                  }
               }
            }
         ]
      }

   2. Edit the JSON by providing values for the destination bucket owner account ID and IAM-role-ARN. Save the changes.

   3. To add the replication configuration to the source bucket, run the following command. Provide the source bucket name.

      $ aws s3api put-bucket-replication \
      --replication-configuration file://replication.json \
      --bucket source \
      --profile acctA

7. Check replica ownership in the Amazon S3 console.

   1. Sign in to the AWS Management Console and open the Amazon S3 console at https://console.aws.amazon.com/s3/.

   2. Add objects to the source bucket. Verify that the destination bucket contains the object replicas and that the ownership of the replicas has changed to the AWS account that owns the destination bucket.