[Discussion] Is USB Backup using the .ter_sys folder for mirrored backups? [SOLVED]

[AGiLiT]

I set up a USB backup task in mirror mode to backup files from my NAS (F4-425 Plus, TOS 7.0.0392) to my DAS DS 2-310. I noticed during the initial run that I was getting a lot of strangely named files getting copied and it was taking a long time. When the first run finished, I noticed the size of the backup on the DAS was twice the size of the files backed up. I was able to see using an external file manager on the NAS that there was a hidden .ter_sys directory in the shared folder that was apparently the size of all the One of the subdirectories in the USB Backup source is also being synced via. TerraSync to my PC, but its contents are pretty small.

So: I understood that TerraSync is using the .ter_sys sytem folder to manage file synchronization. Is USB backup also using the same mechanism? It there a way to do a NAS to DAS backup that is more efficient in utilizing disk space?

[CursaYang]

The directory you backed up is in the same location as the terrasync team folder, and this .ter_sys serves as a snapshot directory for terrasync. Therefore, the size of your backup is doubled. You can separate the backup directory and then perform the backup again. We will also optimize this in the future by automatically filtering out this file.

[AGiLiT]

I don't quite understand your suggestion. To expand on my setup a bit, my file structure looks like this:

Volume1
/Media (this is a shared folder)
/Audio
/Library1
...
/Video
/Photo

There are also the #recycle and (very well hidden) .ter_sys folders under /Media.

The /Media directory is the backup source for USB backup.
The /Media/Audio/Library1 directory is the remote directory for the TerraSync sync task.
The .ter_sys folder is the size of the Audio, Video, and Photo directories under the Media folder; not the size of the (much smaller) Library1 folder.

So: when you say to separate the backup directory, what exactly do you mean? Move folders from /Media? Given that Library1 is a subdirectory under Media, won't the .ter_sys folder follow it wherever it is?

[TMzethar]

Learning that you are still confused, we may need to continue to understand your true intention. Are you hoping that the hidden directory will not be read and backed up by the USB Copy backup task? We might discuss and attempt to implement this in future versions. If you are referring to other issues, please describe the relevant content as much as possible and provide screenshots.

[AGiLiT]

Yes; it would be wonderful if the hidden directory would not be backed up by USB copy. Since the odds are any USB device used for backup purposes will not have the same storage capacities as the NAS, doubling the size of backups is kind of self-defeating.

The other thing I am referring to is not an issue: I am simply trying to clarify if USB backup is 'working as designed'. All the references I have seen to the .ter_sys directory refer to it in relation to TerraSync; such as being the snapshot directory for TerraSync. I have not seen any reference to it being related to USB backup. However, the only way I can understand the .ter_sys size I am seeing is if USB backup is using the same mechanism as TerraSync and/or using the same directory to manage its backups; at least if it is a mirrored backup. That is why I flagged this post not as an issue, but for discussion of the best way utilize USB backup. For instance, would performing an incremental backup use less space on the initial backup than a mirrored backup? What about if I remove the TerraSync sync task, would the .ter_sys folder disappear? That's the kind of information I was looking for.

I do appreciate your followup. I hope this clarifies things.

[CursaYang]

This is unrelated to the mode used by USB Copy. Fundamentally, it is because the backup directory you selected includes the TerraSync directory. You can exclude the .ter_sys directory when choosing the backup directory as a temporary solution. We will optimize the filtering mechanism in subsequent versions.
To remove the Terrasync synchronization task, you also need to remove this directory from the team directory for the .ter_sys folder to disappear.

[AGiLiT]

The .ter_sys directory is not visible, even with 'show hidden files' checked and therefore cannot be excluded from the backup.

I figured out what is going on. It is a TerraSync issue, so I will take it there. Still, it would be a very significant enhancement if the .ter_sys diectory could be excluded from USB backups. Thanks.

[GevinKe]

Thank you very much for your feedback!
We have promptly confirmed and recorded this issue, and the related fix has already been added to our development schedule and will be optimized in a future release as soon as possible.
Your understanding and support mean a great deal to us—thank you again!

[AGiLiT]

Hooray! Very happy to see that this has been made included in the 7.0.043 release. I tested and seems to be working just fine. Thank you!

[OrionXie]

Cheers! Thank you for your feedback. Your affirmation is our greatest motivation. Wishing you a wonderful day.