Files backed up again

[Lennart_T]

I run Retrospect 15.6.1 on Mac OS X 10.11.6.

I had my media files (audio and video) on an external USB hard drive connected to my Airport Extreme. I did have some problems with unchanged files being backed up again and again, but I didn't really investigate since I was about to buy a NAS.

Now I have a Synology DS218j as a NAS server. The audio and video files were copied over to the NAS, 2.1 TB in total.

Then I ran a Retrospect backup with the Synology volume as the source to a media set that I had been using. 1.7 TB of files were backed up. Fair enough, since the metadata probably has changed.

Then I immediately tried another backup from the Synololgy to the same media set. Retrospect wanted to backup a whopping 723 GB again. Why? What is going on?

Is there a way to get Retrospect to tell me why it thinks it needs to backup all those files and what can I do about it?

Bonus question: Is there a utility that can check and correct the file dates (for instance) so they are not somewhere in the future? I have TechTool Pro 11, but that does not seems to do the trick.

[Nigel Smith]

17 hours ago, Lennart_T said:

Now I have a Synology DS218j as a NAS server. The audio and video files were copied over to the NAS, 2.1 TB in total.

What's the Synology volume formatted as? (btrfs can do funky things with metadata, as mentioned in a previous thread.) Did you make any service changes on the Synology between the backups? Are the Synology and Retrospect clocks in sync and in the same time zone (only thinking of that because we in the UK have just switched from BST, which often caused problems in the past 😉 ).

17 hours ago, Lennart_T said:

Is there a way to get Retrospect to tell me why it thinks it needs to backup all those files and what can I do about it?

AFAIK, we don't have the equivalent of the RS Windows's "Preview" when backing up. You might be able to tell after the fact by restoring the same file from both snapshots and comparing them and their metadata. Or winding the log levels up to max and sorting through all the dross for some information gems -- you'll want to define a "Favo(u)rite" with just a few files for that, though!

17 hours ago, Lennart_T said:

Bonus question: Is there a utility that can check and correct the file dates (for instance) so they are not somewhere in the future? I have TechTool Pro 11, but that does not seems to do the trick.

Terminal?

find . -ctime -1s

...will find "future modified" files (I think -- tricky to test!) in the current working directory and deeper. "-ctime" is the most inclusive "change", including file modification, permissions and ownership.

What do then want to do? If it's just "set modification time to now" then

find . -ctime -1s -exec touch {} \;

...should do the job.

That's working with the Synology mounted on your Mac. If you want to do it directly on the Synology, which is probably faster/better but assumes you can ssh in, then this should work with its "idiosyncratic" version of *nix:

touch timeStamp.txt;find . -newer timeStamp.txt -exec touch {} \;

...where we're creating a file with a mod time of "now", finding all files newer than that (ie timestamped in the future), and setting their mod times to "now".

All the above works on my setup here but, as always, you should test on something you can easily restore if it all goes pear-shaped...

[Lennart_T]

Hello and thanks for answering.

6 hours ago, Nigel Smith said:

What's the Synology volume formatted as?

A bit of digging revealed: "ext4"

6 hours ago, Nigel Smith said:

Did you make any service changes on the Synology between the backups?

No, I did not.

6 hours ago, Nigel Smith said:

Are the Synology and Retrospect clocks in sync and in the same time zone

Yes (even within the same second) and yes.

6 hours ago, Nigel Smith said:

Terminal?

find . -ctime -1s

...will find "future modified" files (I think -- tricky to test!) in the current working directory and deeper. "-ctime" is the most inclusive "change", including file modification, permissions and ownership.

Only two files inside an application package (and they are quite small).

I will try SSH later.

6 hours ago, Nigel Smith said:

All the above works on my setup here but, as always, you should test on something you can easily restore if it all goes pear-shaped...

I do have both the original disk I copied over to the NAS as well as backups.  

 

Do you think turning up logging in the "secret settings" will show anything useful?

I will try a favo(u)rite folder with that.

Regards,

Lennart

[Lennart_T]

I found a solution, which work since this is just a data disk, not a system disk.

[Nigel Smith]

I always thought those options applied to sources with the RS Client installed, rather than non-client shares -- or does it consider the share to be mounted on a client which also happens to be the server? I'd certainly never think of changing options in the "Macintosh" section when backing up a Synology, however it was attached!

Every day's a learning day 🙂