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  1. Home
  2. NetBackup™ Deduplication Guide
  3. MSDP cloud support
  4. About MSDP cloud immutable (WORM) storage support
  5. About immutable object support for AWS S3
  6. About bucket policy for immutable storage
NetBackup™ Deduplication Guide

About bucket policy for immutable storage

Bucket policy protects the metadata objects of immutable storage, such as lockdown-mode.conf and lsu-worm.conf for each volume or sub-bucket. Bucket policy is created and updated automatically when cloud immutable volume is created.

If the bucket already has some bucket policy, cloud administrator needs to merge the existing bucket policy with the policy for immutable storage manually. For information about editing the S3 bucket policy, see Adding a bucket policy using the Amazon S3 console topic in the AWS documentation.

Following is the example of bucket policy for immutable storage in AWS S3.

{
    "Version": "2012-10-17",
    "Id": "vtas-lockdown-mode-file-protection",
    "Statement": [
        {
            "Sid": "vrts-lockdown-file-read-only",
            "Effect": "Deny",
            "Principal": "*",
            "Action": [
                "s3:DeleteObject",
                "s3:PutObject",
                "s3:PutObjectRetention"
            ],
            "Resource": [
                "arn:aws:s3:::bucket-name/volume-name/lockdown-mode.conf",
                "arn:aws:s3:::bucket-name/volume-name/lsu-worm.conf",
                "arn:aws:s3:::bucket-name/volume-name/lockdown-mode.conf",
                "arn:aws:s3:::bucket-name/volume-name/lsu-worm.conf",
                "arn:aws:s3:::bucket-name/volume-name/lockdown-mode.conf",
                "arn:aws:s3:::bucket-name/volume-name/lsu-worm.conf"
            ],
            "Condition": {
                "StringNotEquals": {
                    "aws:userid": "YOUR-USER-ID-HERE"
                }
            }
        }
    ]
}

See Troubleshooting the error when the bucket is created without msdpcldutil .

See AWS user permissions to create the cloud immutable volume.

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