Time Machine and Secure Empty Trash
October 25th, 2007 by admin
This Leopard review points out something that has troubled me since I first heard of Time Machine:
Unfortunately, Time Machine has a serious problem: there is no way (that I can find) to remove a file from a Time Machine backup. This is a pretty glaring omission. After all, Leopard has a “secure empty trash” feature that lets you throw away files so that they can’t be recovered with forensic tools. What’s the point of erasing a file on the hard drive and then overwriting the disk sectors seven times if Leopard is going to keep a copy of the file in the Time Machine backup?
Agreed. It seems like while handy to have backups, sometimes you just want a file totally gone. Though, I store anything sensitive (like financial items, etc.) on an encrypted disk image. However, if Time Machine is backing things up every hour – it could grab such a file before one has time to copy to a secure disk image. So, while you can turn Time Machine off for specific folders, etc – it’d still be nice to have some way to obliterate all copies of a file from the past, as well as the future.
You can delete all backups though I doubt they’re done “securely” with overwrites. See below.
Brian Marquis Says
You can delete files from a time machine backup: 1. Navigate to the file you want to delete 2. Activate Time Machine 3. Choose Delete All from the action menu.
You can also delete files that are only in Time Machine. Click on the finder, then reverse steps 1 and 2 above.
Oct 28th, 2007 at 2:51 pm
Marcos Says
Nice! Thanks for the tip!
Oct 29th, 2007 at 12:13 pm
ps Says
Though, the question is: whether deletion is done ’securely’, ie by overwriting the file content several times. I doubt, any ideas how can it be done?
One that comes to my mind, it to remove the file as described, then run Disk Tool/Utility (I don’t remember exact name) and clean unused space securely.
Dec 3rd, 2009 at 6:52 pm