1. Oracle ZFS Storage Appliance Administration Guide, Release OS8.8.x
  2. Shares and Projects
  3. File Retention Management
  4. Planning Guidelines for File Retention

Planning Guidelines for File Retention

When planning for file retention, observe the following guidelines:

  • Mandatory file retention affects the filesystem, project, and storage pool. Carefully plan mandatory usage so that storage resources, especially pools and their associated drives, are not consumed for longer than necessary or overfilled. Note that to rename a storage pool, you must unconfigure it and then immediately import it with a new name. You cannot unconfigure a storage pool with mandatorily retained datasets.

  • If you think there is a risk of someone unconfiguring a storage pool to destroy it at the same time that someone else is wrongly adding a mandatorily retained filesystem or project to the storage pool, set the maximum file retention period to a higher value.

  • For mandatory file retention, the storage pool profile must provide redundancy. Therefore, the striped profile cannot be used with storage pools with mandatorily retained files.

  • Directories cannot be renamed until all retained files within them have been deleted or moved to another directory. This preserves the name of the retained file, including its path.

File retention affects filesystem functionality in the following areas:

  • Editing - Although a retained file cannot be modified, a user with role authorization retentionPeriods can edit a filesystem to change the retention periods only, not including the grace period. To edit the grace period, a user must have role authorization retentionAuto.
  • Deleting - A filesystem with privileged retention can be deleted at any time, even if unexpired files exist. A filesystem with mandatory retention can be deleted after all of its files have expired. A file with the file retention on expiry policy set to hold can be deleted when the policy is set to other than hold.
  • Moving - A filesystem with privileged or mandatory file retention can be moved to another project.
  • Renaming - A file or project with privileged or mandatory file retention cannot be renamed, neither when file retention is active nor after the retention has expired.
  • Snapshots:
    • Editing, Deleting, Moving, Renaming - The same principles apply as for retained files and projects not within a snapshot.
    • Cloning - A snapshot containing a filesystem with retention can be cloned. A file with mandatory retention protects its ancestors and clone descendants from destruction. The hold setting for the file retention on expiry policy applies to clones.
    • Rollback - Rollback can be performed on a filesystem with the privileged retention policy, even when unexpired retained files exist. Filesystems with the mandatory retention policy can never be rolled back, even when all retained files have expired.
  • Cloud Backup - When a retained filesystem or project is used as the snapshot for a cloud backup, the same retention principles apply. Additionally, snapshots, themselves, can support snapshot retention. For more information, see Taking a Snapshot - BUI, CLI.

  • Remote Replication - Snapshots of a retained filesystem or project have the same constraints as the file retention feature. Also, the parent and children of a snapshot containing a retained filesystem or project follow the same rules.

    When replicating to a target appliance, that appliance must support the file retention feature by accepting the File Retention deferred update, available with software version OS8.8.45 or later. When replicating to a different storage pool on the same appliance, the target pool must have a redundant profile for a file with mandatory retention. Therefore, the striped profile cannot be used with storage pools with mandatorily retained files. When replicating to an NFS server for offline replication, file retention is maintained.

    Reverse replication is not supported to a filesystem with mandatory retention. This action would require rolling back the filesystem prior to the replication reversal, which is not allowed.

    The hold setting for the file retention on expiry policy does not affect filesystems within a replication package nor does it affect the storage pool containing such replication packages.

  • Appliance Factory Reset - The appliance factory reset feature is disabled if actively retained filesystems exist with mandatory file retention.