Time Machine doing full backups every time

I am going to speculate that the repeating of a full backup has to do with the configuration of the NAS that has been in the path for all these backups. I did not even think one could do Time Machine backups under Sequoia to anything other than APFS (or HFS+ if inherited from earlier versions of the MacOS). Somehow the way the NAS is formatted might be interfering with the normal process that Time Machine uses when it checks whether the existing Time Machine backup is up to date versus recent changes on your source drive.

To check my conjecture, take a USB external drive, format it fresh as APFS, connect it DIRECTLY to the Mac via one of its USB or Thunderbolt or USB-C ports and a cable, and tell it to back up to that drive. This is to verify that in this configuration, repeated backups are quick incremental backups. If it works properly, that would indicate that troubleshooting for your NAS setup is needed as the next step. I don't use NAS so can't offer much guidance for that, but many others who are involved here on Discussions do.

Have you verified that you can indeed restore specified files and folders from your NAS Time Machine backups? I am wondering about the integrity of those backups since they don't seem to be properly recognized (full backups every time).

arthur wrote:

That it is doing 30GB+ with each backup, and it takes the better part of an hour. Even if I start a manual backup within one minute of the last backup being done, and I haven't changed anything.

I see the same thing....

I even erase/ reformatted as GUID /APFS case sensitive— which is what TM makes it) started a new TM BU all in an effort to minimize each subsequent BU. No dice.

My BU disk space is declining in chunks...

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What data er you looking at to conclude it is doing a full backup over and over? It will always scan all to find any file changes and then copy those changes which may look like it is doing all over again but in reality it is not.

tbirdvet wrote:

I do not see that on mine. Each of my incremental backups are small. My drive is formatted APFS, case sensitive, encrypted.

thanks tbirdvet— maybe that is answer

I did not do the encrypted part—that might have been a mistake. I know it will encrypt the back up on the fly (mandatory default), but maybe that is the key to reformat case sensitive & encrypt from the get go and then present it to the TM as the backup destination.

Any thing else I have never done case sensitive, or encrypted on my internal drive. I have no Government secrets...and case sensitive seems illogical in the big picture.

I might have to try again and start fresh to compare those results.

I do not see that on mine. Each of my incremental backups are small. My drive is formatted APFS, case sensitive, encrypted.