A Time-Machine tmutil compare
with HFS backups (e.g. on High Sierra or Catalina) allows evaluating the differences between two backups by doing:
cd "${tmutil machinedirectory)"
tmutil compare 2022-01-23-170921 2022-19-064128
This fails on an APFS backup volume (e.g. on Monterey).
How do I compare two backups from an APFS-based Time Machine as is done with HFS+ Time Machine backups? Consider:
Output of tmutil listbackups
2022-01-19-111302.backup
2022-01-21-115629.backup
2022-01-23-080851.backup
2022-01-26-085332.backup
Output of tmutil machinedirectory
/Volumes/JRF_MBP_Backup
Output of ls -al /Volumes
drwxr-xr-x 3 root wheel 96 Jan 26 09:23 .timemachine
drwxrwxr-x@ 5 root wheel 160 Jan 26 09:23 JRF_MBP_Backup
lrwxr-xr-x 1 root wheel 1 Jan 23 07:26 Macintosh HD -> /
Unlike an HFS Time-Machine backup volume, no objects matching those of listbackups
can be seen in the machinedirectory
directory using simple ls
command.
Output of ls -al /Volumes/JRF_MBP_Backup
drwx------ 4 jrf staff 128 Jan 19 08:30 .Spotlight-V100
drwxr-xr-x@ 5 root wheel 160 Jan 26 08:53 2022-01-26-085332.previous
-rw-r--r--@ 1 root wheel 1964 Jan 26 08:53 backup_manifest.plist
Instead, examining the /Volumes/.timemachine
directory shows subordinate objects that correspond to listbackups
.
Output of ls -al /Volumes/.timemachine/7DF818BF-10AE-48F6-B709-4EAB88C58D16
drwxrwxr-x@ 4 root wheel 128 Jan 19 11:13 2022-01-19-111302.backup
drwxrwxr-x@ 5 root wheel 160 Jan 21 11:56 2022-01-21-115629.backup
drwxrwxr-x@ 5 root wheel 160 Jan 23 08:08 2022-01-23-080851.backup
drwxrwxr-x@ 5 root wheel 160 Jan 26 08:53 2022-01-26-085332.backup
It seems reasonable, therefore, to do (for example):
cd /Volumes/.timemachine/7DF818BF-10AE-48F6-B709-4EAB88C58D16
tmutil compare 2022-01-23-080851.backup 2022-01-26-085332.backup
But, this fails:
Can't compare a source volume to a source volume.
Usage: tmutil compare [-@acdefghlmnstuEX] [-D depth] [-I name]
tmutil compare [-@acdefghlmnstuEX] [-D depth] [-I name] snapshot_path
tmutil compare [-@acdefghlmnstuEUX] [-D depth] [-I name] path1 path2
How do I compare two backups from an APFS-based Time Machine as is done with a HFS+ Time Machine backups?