Unable to backup macbook using time machine Since a few weeks ago, i am unable to backup my mac using time machine. It finds my backup drive, but each time i get a message that reads : failed to create a local snapshot.
I have already reinstalled a fresh installation using the apple recovery utility, and also tried to use a different backup drive.
Note that i did not try to erase my data yet.
Edit:
I wanted to point out the fact that this issue is impacting two macbook at this time, while six others are being backed up fine, using the same release and the same backup disc.
Edit:
Using this command sudo tmutil listlocalsnapshots /, I get this output:
Snapshots for volume group containing disk /:
com.apple.TimeMachine.2020-06-18-194222.local
com.apple.TimeMachine.2020-06-18-203811.local
com.apple.TimeMachine.2020-06-18-213808.local
com.apple.TimeMachine.2020-06-18-223858.local
com.apple.TimeMachine.2020-06-18-233809.local
com.apple.TimeMachine.2020-06-19-004440.local
com.apple.TimeMachine.2020-06-19-014255.local
com.apple.TimeMachine.2020-06-19-024125.local
com.apple.TimeMachine.2020-06-19-033808.local
com.apple.TimeMachine.2020-06-19-043810.local
com.apple.TimeMachine.2020-06-19-053809.local
com.apple.TimeMachine.2020-06-19-064356.local
com.apple.TimeMachine.2020-06-19-083809.local
com.apple.TimeMachine.2020-06-19-095017.local
com.apple.TimeMachine.2020-06-19-104256.local

So, snapshots are indeed created despite time-machine's error message.
As suggested, the only solution was to back up the whole system using a rsync command, and reinstall the OS from scratch.