not enough space for TM backup

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Level 1

17 points

not enough space for TM backup

Hello and good day to you all,

I am running El Cap on an iMac with a 2 TB fusion drive, out of which only about 450 GB are in use.

TimeMachine stopped backing up due to lack of space - there are only 15GB left on my 500 GB backup drive. Apparently the last backup took up most of the drive, and it won't let me delete anything.

I've excluded 200 GB worth of files from being backed up, and cleared a ton of app Cache (in case that was also being backed up) and now the total volume that needs backup is about 300 GB.

TM is still giving me the same error message.

I also tried resetting TM preferences - to no avail.

Is there something else I can do rather than erasing the backup drive and starting from scratch?

Thanks!

iMac, OS X El Capitan (10.11.6), 27 Late 2015 iMac, 2TB

Posted on Dec 11, 2017 9:07 AM

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Answer 1

Best reply

Drew Reece

Level 6

10,660 points

Dec 11, 2017 11:49 AM in response to dndn

dndn wrote:

I've deleted and excluded almost half of the data that was being backed up. I just don't get it....

How have you deleted the data? In Finder or via the 'Enter Time Machine' feature of Time Machine.

Time Machine is a complex system of duplicates & pointers to original data, as den.thed mentioned you can't delete correctly in Finder. Open the location in the Time Machine UI & right click (or use the gear menu) to remove all backups of xxx.

Do you have other backups in place? Personally I find Time Machine is best left to do as it pleases otherwise it can simply mess up when a lot of new data is added to the OS & decide to remove a lot of history (and warns you after the deleting has happened). If you want better control over how much data to keep consider using an app like Carbon Copy Cloner, it can clone an OS to a bootable disk but also keep older versions too with a limit on the space that they take.

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Answer 2

den.thed

Level 9

77,230 points

Dec 11, 2017 10:39 AM in response to dndn

dndn wrote:

Is there something else I can do rather than erasing the backup drive and starting from scratch?

Yes' get a larger External Hard Drive for Time Machine.

see > http://web.archive.org/web/20170609220958/http://pondini.org/TM/1.html

How to use Time Machine to back up or restore your Mac - Apple Support

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Answer 3

dndn Author

Level 1

17 points

Dec 11, 2017 12:50 PM in response to den.thed

Thanks you so much. You are right, of course, that this is the general recommendation, but I don't store that much data on my internal drive (I keep all my large files on external drives) and it says in the article that 1.5 times the space can suffice. I've been using this backup HD successfully since I got this computer (about a year ago) and I'd rather not spend the money on a larger drive...

I can't understand how it was backing up fine all this time with much more data...

I've deleted and excluded almost half of the data that was being backed up. I just don't get it....

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Answer 4

den.thed

Level 9

77,230 points

Dec 11, 2017 11:07 AM in response to dndn

Because each new backup requires a little more space.

The choice is yours.

If you plan on have continues backup for a long period of time, then you really need a larger drive.

If you do not care about keeping older backups, then keep using a smaller drive and starting over when it full.

FWIW to start over, you will need to completely erase the backup drive using Disk Utility.

Do not try and delete any of the backups via Finder, because your Trash will choke on it.

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Answer 5

dndn Author

Level 1

17 points

Dec 11, 2017 1:05 PM in response to Drew Reece

Thanks for explaining me how to delete the backed up files. It worked! TM is now backing up 🙂

I do have other backups and therefore I excluded these files from TM backups. These are finished projects and photos that won't be altered anymore, so there's no added value to backing them up via TM.

Thank you so much!

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Answer 6

dndn Author

Level 1

17 points

Dec 11, 2017 1:11 PM in response to den.thed

Thanks for explaining this. If it happens again, I may have to erase the disk and start over, but for now, deleting older backups seems to be the answer. I'll also exclude the cache files from my next backups. I think they were the main problem.

Thank you so much!

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