A while back I set a client up with a backup solution that used the native Windows 7 backup utility to copy local files to a Raid 1 mirrored array.
And actually, I remapped all his documents and libraries to this raid 1 array and kept program data like his .pst and quickbooks files on the system drive so I only needed the backup utility to copy his outlook .pst (2 gigs) and quickbooks company files (1 gig) over to the mirrored array.
Flash forward 3 months later and this client calls and tells me his 500 gig backup drives are completely full and Windows is complaining about no disk space.
Thus, I crack open the backup utility and take a look at how this thing is making backups. To my surprise, it was duplicating the data every single day. So everyday, it was making completely new backups of his 2 gig .pst and 1 gig QB company files.
Further research suggests Windows 7 uses a block based backup system and even deeper research yields people who say this is a "differential" backup method and others who suggest something like "it makes duplicates"
How does this backup system work and is it a viable solution for data files that are quite large and change everyday?