My Time Machine is suddenly not backing up and giving me the message: "Time Machine could not create a local snapshot to back up from because there was insufficient free space on the source volume(s)." I have an iMac running Mohave (if that matters).
So, how much Free Space on the Internal Drive? Do a Get Info in Finder.
Have you emptied the Trash Lately?
Purging local backups
Please note that although this doesn't affect your remote backup from Time Machine, this will get rid of the redundancy (at least until the next Time Machine backup) that a local backup disk will provide. If you need such redundancy or are worried about the recovery of your data then you would be best served to let macOS determine when to purge these files.
Start Terminal from spotlight.
At the terminal type tmutil listlocalsnapshotdates.
Hit enter.
Here, you'll now see a list of all of the locally stored Time Machine backup snapshots stored on your disk.
Next you can remove the snapshots based on their date. I prefer to delete them one at at time. Once my "System" disk usage is at an acceptable level, I stop deleting but you can delete all of them if you want to reclaim all of the disk space.
Back at the terminal, type tmutil deletelocalsnapshots YYYY-MM-DD-HHMMSS , where will be one of the dates from your backup. This will be in the form of xxx-yy-zz-abcdef. Try to start with the oldest snapshot.
Hit enter.
Repeat for as many snapshot dates as required
http://www.thagomizer.com/blog/2018/03/27/cleaning-up-time-machine-local-snapshots.html
So, how much Free Space on the Internal Drive? Do a Get Info in Finder.
Have you emptied the Trash Lately?
Purging local backups
Please note that although this doesn't affect your remote backup from Time Machine, this will get rid of the redundancy (at least until the next Time Machine backup) that a local backup disk will provide. If you need such redundancy or are worried about the recovery of your data then you would be best served to let macOS determine when to purge these files.
Start Terminal from spotlight.
At the terminal type tmutil listlocalsnapshotdates.
Hit enter.
Here, you'll now see a list of all of the locally stored Time Machine backup snapshots stored on your disk.
Next you can remove the snapshots based on their date. I prefer to delete them one at at time. Once my "System" disk usage is at an acceptable level, I stop deleting but you can delete all of them if you want to reclaim all of the disk space.
Back at the terminal, type tmutil deletelocalsnapshots YYYY-MM-DD-HHMMSS , where will be one of the dates from your backup. This will be in the form of xxx-yy-zz-abcdef. Try to start with the oldest snapshot.
Hit enter.
Repeat for as many snapshot dates as required
http://www.thagomizer.com/blog/2018/03/27/cleaning-up-time-machine-local-snapshots.html
I'm having the same problem all of a sudden. I am trying to backup my 500GB MacBook Pro to a 2TB volume. The big deal, apparently, is space available on the source drive. I found that having less than 15-20GB makes Time Machine choke.
It seems odd to me that that info is kept on the source drive, and not the backup drive (where there's ostensibly more space for it), but my bet is that's the source of your problems.
I'd worry less about clearing off Time Machine snapshots and instead get rid of things on your hard drive that you don't need. One thing I've found takes up HUGE amounts of space is video files exported from iMovie, Motion, FCP, things like that. I've been systematically going through looking for any stupid 15- or 20-minute video that's inexplicably taking up 1.5 GB of space on my hard drive, Handbrake-ing it down to around 350MB, and getting rid of the uncompressed behemoth. But YMMV.
OmniDiskSweeper shows you the files on your drive, largest to smallest, and lets you quickly Trash or open them.
When I type that in terminal, nothing shows up. This means that I have not snapshots on the local disk? Any other ideas or do I just have too much stuff on my hard drive?
Time Machine can't complete backup
