NAS Recycle Bin impact on Veeam Backup & Replication Repositories

As Backup or Backup Copy jobs run targeting an SMB share on a NAS where the Recycle Bin* is enabled, the metadata files (VBM) can become captured in that Recycle Bin folder. Over time this may cause the following side-effects:

• Repository Rescan completion time takes longer as more restore points are created.
• Many duplicate backup datasets appear under the Backups > Disk (Imported) section.
• The configuration database may exceed the SQL Express 10GB limitation.

*The exact feature name may vary depending on the storage vendor. For example, one NAS vendor calls this a "Trashbox"

The underlying reason this issue occurs is that when a Backup or Backup Copy job needs to update the VBM file, rather than modify the known good VBM, a temporary VBM is written to disk. Then, once the write operation is completed, the old VBM is deleted, and the new VBM is renamed. When the Recycle Bin feature is enabled on a NAS, it may capture these deleted VBM files in the Recycle Bin (e.g., @recycle or #recycle). When a Repository within Veeam Backup & Replication is configured to use a path that contains the Recycle Bin (even if hidden), the content of that folder will be scanned during a rescan. The rescan operation recursively searches all folders in the Repository path, looking for VBM files. If a VBM file is located in the Recycle Bin, the rescan operation will create a database entry for the found VBM file and an entry within the UI's Backups > Disk (Imported) section.

Examples:

• An SMB repository configured to use the root of the share (e.g., \\<hostname>\<sharename>\), causing Veeam Backup & Replication to scan the Recycle Bin if enabled in the NAS settings.

If an existing SMB Share repository is experiencing the side effects described in the Challenge section of this article, do the following:

1. Disable and Empty the Recycle Bin on the NAS for the share used by Veeam Backup & Replication.
   (Reference the storage vendors' documentation for information on how to do this.)
2. Remove from configuration all duplicate entries listed under Backups > Disk (Imported)

If you are building a new Repository for an SMB share on a NAS device, it is advisable to create a dedicated backup folder within the share and use that as part of the path when creating the repository (e.g., \\<hostname>\<sharename>\Backups\).

If the share path used by the Veeam Backup & Replication Repository is also used for other non-Veeam data, the rescan operation will scan those folders, causing Rescan operations to take an excessive amount of time to complete. To mitigate this situation, create a dedicated folder for backups on the share (e.g., \\<hostname>\<sharename>\Backups\) and move Veeam Backup & Replication Backup Files.

For performance reasons, it is best to make sure that the path provided for repositories in Veeam Backup & Replication is that of a dedicated folder containing only backup files.

Note that the "Problematic" path examples are problematic only because there can be files other than Veeam's backup files placed in those paths, meaning that when Veeam Backup & Replication performs a rescan operation, it has to review irrelevant data.