Copying Time Machine backups to new drive increases the size

[speckay]

Hi there,

Not sure where else to turn, but hopefully someone else knows how to fix this issue. I had bad RAM on an iMac corrupt my external TM backup drive. So now TM says I can't use write to it but it will mount so that I can copy files off. In the process of copying the Backups.backupdb folder using a new iMac, I noticed it's blowing up to >4x larger on the new drive. I'm basically running out of space and can't copy the backups (~500 GB of backups has filled a 2 TB drive with only 1/2 of the data copied).

Anyone know how to fix this issue? I've tried copying via Finder, as well as using cp and rsync. I'm tempted to just copy the disk image to see if that solves it... but I absolutely need this data and unmounting and remounting already takes forever, it's making me nervous.


Thanks!

Kristin

 

[BrianBaughn]

You might be able to use Disk Utility to "Restore" the TM partition to a new disk image...I'm not sure. You can definitely restore it to a new drive or partition, giving the new one the proper amount of space.

The problem that you're having is because the TM backup folders contain multiple "Hard Links" to identical files. The hard links take up very little space but the Finder sees them as actual files. It's fundamental to how Time Machine works.

If you don't mind not having the version history of your files and files you have deleted (the stuff you can get via Time Machine) you could just copy the latest backup folder in that TM backup folder. Or, being even more selective, just get what you need out of that folder.

 

[speckay]

Awesome, thanks. I wasn't sure about the whole hard links situation.

I managed to make an image via Disk Utility and I'm trying to restore now to a new external HD, then I'll see if I can use the recovery partition to restore my iMac via Time Machine.