Backup keeps including all files

[hevanw]

One of my backup scripts does the following : it back ups my entire NAS (8 shares in total) to an external 4TB hard disk. This script runs once a week. It now looks like every time the script runs, the entire NAS is written to the disk rather than only the changed/new files.

 

The backup set has the following options: Block level incremental backup, Media verification, Data compression, Match source volumes to Catalog File, Don't add duplicates to Backup Set.

 

The catalog files are stored on my Retrospect Server, and the 4TB backup target is an external USB disk.

 

The one thing that I can imagine having an impact, is that the NAS shares are mounted on the Retrospect Server as read-only. But even with 'Match only files in same location' being unchecked, I would think this should not have an impact. Retrospect should match any file from the NAS with what is already in the backup set and thus not backup the same file over and over again ?

 

Note that in total I have 6 backup scripts and sets and this is the only script that is behaving like this. It's however also the only script where data from the NAS is being backed up.

[Scillonian]

What is the make and model of your NAS?

 

If it is a Linux based NAS then the problem could be because the Windows file system that the Retrospect Server sees is an emulation running on top of the underlying Linux file system.

 

Depending on the capabilities of you NAS a better solution may be a backup to the external drive directly from the NAS instead of using Retrospect over network shares. NAS manufacturers such as QNAP and Synology provide Apps to backup NAS shares to external drives.

[hevanw]

Thanks for the suggestion ! I can indeed look into connecting the disk through USB on the NAS as that USB disk is only used as a disaster recovery backup of the NAS. The NAS is a Synology DS418j.

 

Still a bit confused though why the matching fails. Isn't the matching supposed to do a comparison file-by-file or even block-by-block (since I have Block Level enabled) based on hashes ? Retrospect is even not supposed to write a full file if it is found elsewhere on the filesystem as well (unless that 'path match' option is enabled).

The files have not changed, so the underlying file system should not matter.

[Scillonian]

I think the Block Level Incremental Backup only works for backups of volumes on physical disks connected to the Backup Server itself or client computers when they are accesses through the Retrospect Client. As far as I know only file level backup is available for volumes on network shares.

 

Another area worth checking in the Backup Script is the settings for the backup of file and folder security information. In the settings dialog for the Backup Script they are at Options > Windows > Security. If anything changes in the security information for a file or folder and Retrospect is set to backup security information the file will be backed-up again even though the file itself has not changed.

 

I have a QNAP NAS which I use as the destination for my Retrospect Backup Sets and general file storage. I use the 'Backup Station' utility on the NAS to backup the shares to ext4 formatted external disks four times a month. The reason I use ext4 formatted disks is to ensure the files, folders, and their metadata are copied 'as is' from the NAS.

[hevanw]

 

Another area worth checking in the Backup Script is the settings for the backup of file and folder security information. In the settings dialog for the Backup Script they are at Options > Windows > Security. If anything changes in the security information for a file or folder and Retrospect is set to backup security information the file will be backed-up again even though the file itself has not changed.

 

 

Thank you ! After some in-depth tests, it was indeed the Security Information that was the culprit. I've now disabled both file and folder options and now only what has truly changed is being backed up.