magicmor.blogg.se

Shadow copies are typically used for backup products.

That’s because when one of these programs says “Give me the data in file X”, Windows starts by reading the shadow-copy version of file X, but then checks to see if any changes have been made if so, those changes get applied before the data is returned to the copy. All the other programs don’t typically know that the shadow copy exists, and they see the changes made since the shadow copy was created. Typically, the program that created the shadow copy is the only one that sees its unchanging contents.

So in other words, the volume is essentially split into two parts: one that holds the contents of the file system at the moment the shadow copy was requested, and one that holds all the changes that have been made since then. While the shadow copy is active, writes to that hard drive don’t overwrite the existing contents of the volume instead, they’re redirected to a special part of the file system. A shadow copy essentially lets a process take a snapshot of a volume (C:, D:, etc.) at any given instant. In order to explain why shadow copies don’t really help us, let me first explain what a shadow copy is.