So I got myself a shiny new Mac Mini, finally got everything transferred over from my old machine, and want to resume backing up using my existing Time Machine disk and backup history (as I've basically transplanted the dead old machine to the new one).
However I just can't get Time Machine to inherit the backup.
Every time I've done this in the past, I would simply choose the volume as a backup disk, and Time Machine would automatically ask me if I wanted to inherit the backup, but it's not doing this this time.
So I tried running the following command instead:
sudo tmutil inheritbackup /Volumes/Backup/Backups.backupdb/Haravikks\ Mac
But I get the following error:
sudo tmutil inheritbackup /Volumes/Backup/Backups.backupdb/Haravikks\ Mac Usage: tmutil inheritbackup machine_directory tmutil inheritbackup sparse_bundle /Volumes/Backup/Backups.backupdb/Haravikks Mac: Invalid target
The older system was running Mojave, while the new one is Catalina.
I've tried associating all of my disks instead (using
tmutil associatedisk /path/to/volume /path/to/snapshot_volume, but if I begin a backup, Time Machine is still determined to start fresh (which I don't have space for) and creates a new machine directory (Haravikks Mac 2), even though the machine name of my new computer is identical.
I've also already given Terminal full disk access (because it's basically useless otherwise, thanks Apple) as that's usually the culprit for other mysterious invalid operations, but
tmutil inheritbackup still won't take.
Is there any way that I can find out why Time Machine/
tmutil consider my old machine directory invalid? There's nothing in the logs, and
tmutil doesn't appear to have a flag for giving more verbose output (unless I've missed it?).
Failing that, is there some way can I force Time Machine to inherit a machine directory?
Update: In case it helps any, I've been noticing a lot of Spotlight related (
mdworker) activity on the disk, strange since nothing is being added to it. Could this be related? Again, this didn't happen under Mojave (the disk would sleep between backups).
Update 2: Thanks so much to klanomath for an explanation of where else Time Machine stores data, here's the
xattr -l listing for my machine directory:
xattr -l /Volumes/Backup/Backups.backupdb/Haravikks\ Mac LastModTime: 1574418303756056852 com.apple.backupd.BackupMachineAddress: 00000000 63 38 3A 62 63 3A 63 38 3A 61 33 3A 33 33 3A 31 |c8:bc:c8:a3:33:1| 00000010 31 00 |1.| 00000012 com.apple.backupd.HasRecoverySet: YES com.apple.backupd.HostUUID: 00000000 39 31 31 42 33 43 37 46 2D 35 42 36 36 2D 35 39 |911B3C7F-5B66-59| 00000010 45 30 2D 39 36 41 43 2D 39 31 42 37 35 38 38 43 |E0-96AC-91B7588C| 00000020 44 43 38 46 00 |DC8F.| 00000025 com.apple.backupd.ModelID: Macmini4,1 com.apple.backupd.RecoverySetName: 0