virtualbox.org

Because my 500 GB hard drive is almost full with quite a few backup points (free space = 27 GB), I wanted to delete some of these backup points. But this is not possible, because the following error is displayed:

"Unable to merge storage 'C:\Users\gerd\VirtualBox VMs\Windows 10 Insider Dev_\Windows 10 Insider Dev_.vdi'. Not enough free storage space."

In Germany, we say "That's probably the cat biting its own tail." On the one hand, I would like to create free space, on the other hand, this is not possible because there is not enough free space. How can I solve this problem?

Specko

You really can't think of a solution? How about: free up some space to a real backup drive and try again?

And incidentally, snapshots are not "backup points". Nothing is backed up. A backup means that you could recover if I zapped your hard drive, or even just one of your snapshot files. You can currently recover from neither of those things - unless you have actual backups that you didn't mention.

And yes, one of the reasons experienced users don't use snapshots is that they do grab massive amounts of host disk space, especially if you don't keep an eye on it, all while not being useful as backups.

Yes, snapshots are alternate VM states, but unlike backups there is no redundant data duplicated across states. No redundancy means you can't recover from a failure means it isn't a backup.

One possible solution: Use 3rd-party backup software, like Macrium Reflect Free, to clone the 500GB drive to a terabyte drive, then switch the drives. Then you'll have room to delete snapshots. And a bonus, if something goes wrong deleting a snapshot you'll have the original VM on the 500GB drive as a backup.