Veeam Backup & Replication allows you to prohibit deletion of data from the extents of the scale-out backup repository by making that data temporarily immutable. It is done for increased security: immutability protects your data from loss as a result of attacks, malware activity or any other injurious actions.
You can enable the immutability feature for any tier of scale-out backup repository.
To learn how immutability works with performance tier of the scale-out backup repository, see Hardened Repository.
To learn how immutability works with capacity tier of the scale-out backup repository, see Immutability for Capacity Tier.
To learn how immutability works with archive tier of the scale-out backup repository, see Immutability for Archive Tier.
In order to use immutability, you need to enable the Object Lock and Versioning features on your S3 bucket at the time you create the bucket. Keep in mind that most vendors allow enabling Object Lock only at the moment of creating the bucket.
For more information on enabling the Object Lock and Versioning features, see these Amazon articles: How do I create an S3 Bucket? and How do I enable or suspend versioning for an S3 bucket?.
For considerations and limitations on immutability, see Considerations and Limitations.