Immutable storage

Immutable storage is a type of data storage that prevents backups from being altered, modified, or deleted for a defined period. It ensures that the data remains secure and tamper-proof, providing an extra layer of protection against unauthorized or unintended modification or ransomware attacks. Immutable storage is available for all cloud backups stored in a supported cloud storage instance. See Supported storages and agents.

With immutable storage, you can access deleted backups during the specified retention period. You can recover content from these backups, but you cannot change, move, or delete them. When the retention period ends, the deleted backups are permanently deleted.

The immutable storage contains the following backups:

  • Backups that are deleted manually.
  • Backups that are deleted automatically, according to the settings in the How long to keep section in a protection plan or the Retention rules section in a cleanup plan.

Deleted backups in the immutable storage still use storage space and are charged accordingly.

Deleted tenants are not charged for any storage, including immutable storage.

Immutable storage modes

Immutable storage is available in the following modes:

  • Governance mode

    You can disable and re-enable the immutable storage. You can change the retention period or switch to Compliance mode.

  • Compliance mode

    Selecting Compliance mode is irreversible.

    You cannot disable the immutable storage. You cannot change the retention period and cannot switch back to Governance mode.

Supported storages and agents

  • Immutable storage is supported only on the cloud storage.

    • Immutable storage is available for Acronis-hosted and Partner-hosted cloud storages that use Acronis Cyber Infrastructure version 4.7.1 or later.
    • All storages that can be used with Acronis Cyber Infrastructure Backup Gateway are supported. For example, Acronis Cyber Infrastructure storage, Amazon S3 and EC2 storages, and Microsoft Azure storage.
    • Immutable storage requires that TCP port 40440 is open for the Backup Gateway service in Acronis Cyber Infrastructure. In version 4.7.1 and later, TCP port 40440 is automatically opened with the Backup (ABGW) public traffic type. For more information about the traffic types, see Acronis Cyber Infrastructure documentation.
  • Immutable storage requires a protection agent version 21.12 (build 15.0.28532) or later.
  • Only TIBX (Version 12) backups are supported.