Adventures with Time Machine

As I mentioned in a previous post, I recently bought an M1 iMac and was having some trouble getting it to recognize the external drive I was using for Time Machine backups. Once I got that solved and set up Time Machine, I noticed that the initial backup would never complete.

The backup would run on schedule, and look like it finished, but “Oldest backup” and “Latest backup” would always say none, and the dropdown from the menu item would always say “waiting for first backup to complete…”.

I started digging and found a TON of people with the same problem (M1-based Macs only, Macs with Intel processors worked fine) and it was always the first backup (re-installing from scratch, setting up a new computer, etc.).

I finally came across a post on the MacRumors forums that suggested running the following command:

log show --style syslog --last 30m --predicate 'senderImagePath contains[cd] "TimeMachine"' --info --debug

At the end of the output, I saw:

localhost backupd[532]: (TimeMachine) [] Backup failed (104: BACKUP_DELAYED_UNFINISHED_PROTECTED_FILES)

This was the same error others were seeing as well. I did two things to solve it:

1) I booted into recovery mode and ran first aid on every partition available (both internal and external).

2) At the suggestion of a bunch of people in the thread, I excluded the following directories from backup:

~/Library/Containers/Find My

Then I manually kicked off a backup and it finished! A few have run since that initial one last night and all have completed successfully. I was hoping this would be fixed with the Monterey 12.1 release, but it’s still an issue. Hopefully Apple fixes it soon so it isn’t necessary to jump through these hoops to get a working backup with Time Machine.