Time Machine - one share, one user, two computers

[danb35]

This problem has been going on for some time, through several versions of CORE and now with SCALE 22.02.4. I've been dealing with it by just increasing the quota periodically, but there has to be a better solution.

I have three Macs that I back up to my NAS using Time Machine: my wife's Macbook Air, and my Macbook Pro and Mac Mini. Her machine backs up to one SMB share, while my two machines back up to another. Both are designated as "Time Machine" shares, and both have filesystem quotas assigned to prevent their filling up the storage pool. Both my Mac Mini and my Macbook Pro have 2 TB of storage, so I've set the quota for that share at 8 TB.

What I expect to happen is that Time Machine will work the way it's supposed to: each machine will make backups every hour, cleaning it out according to its ordinary schedule, and when the "disk is full" (i.e., when the quota is reached on the dataset), it will delete its own oldest backups as necessary to make room for the current backup. And for my Mac Mini, it seems to be working this way--it keeps making backups, and I never see any errors.

But for my Macbook, I get errors that the share is out of space, and it refuses to back up until I add to the share's quota. Once I do that, it will continue to back up in the normal way until the quota's hit again, whereupon it gives the error again.

I'm expecting there's something in the share's settings that's resulting in this behavior, but don't really even know where to start looking. Here's how it's currently configured:

Any thoughts on this?

 

[ChrisRJ]

I am likely stating the obvious. But if the settings on TrueNAS are identical, then there is probably a difference between the computers.

 

[Stux]

I had similar issues. They were resolved when I upgraded the affected macs to Monterey.

(This involved using Open Core Legacy Patcher)

Also, I use per machine logins for each device, rather than owner logins if that makes sense

 

[danb35]

Also, I use per machine logins for each device, rather than owner logins if that makes sense

I just upgraded both affected machines to Ventura, which involved using OCLP for one of them--I'll see if that makes a difference. Right now, though, I'm using a single login for both. If the problem recurs, I'll try this.

 

[garm]

I had this issue on my oldest backup from my 08 iMac, my newer MacBooks never did this, so I suspect its due to the version of TimeMachine when the backup was first created