The approach I take to backups is a very multi-tiered approach. In our office a lot of the concerns about theft or damage to the physical office resulting in a loss of data is mitigated by DFS and the fact that our data is nearly instantly replicated between our offices (located in different cities); the likelihood of anything physically happening to both offices at the same time is very remote.
A far more common danger is user mistakes - files are deleted that shouldn't have been, or changes are overwritten and need to be rolled back. The biggest problem here is the fact that you never know what point in time you'll need to roll back to. Fortunately, Windows Server includes a number of technologies we can take advantage of to be able to handle almost any need that's arisen.
Enter "Shadow Copies". If you use Windows Vista or Windows 7, you may be slightly familiar with this technology; it's called "Previous Versions" in the file properties. The best part, other than the simplicity, is that it's available to any user on the domain - they don't really NEED to ask me to restore this file or that.
Shadow Copies work at the partition level - you keep shadow copies of an entire drive letter or not at all. It works by taking a "snapshot" of the drive when you first set it up, then twice a day (by default) it looks for any files that have been updated since the last snapshot and grabs a copy of the current version. When someone goes into the "Restore Previous Versions" dialog on the client machine, they're presented with a list of all available updates. If they're looking at a file, they'll see just the timestamps of the file when shadow copies saw an update. If they're looking at a whole folder, they'll see every shadow copy time available. In either case, they can restore the file or directory in-place, or open it up to make sure it's the right version, or restore it to an alternate place. It's incredibly useful, and takes a surprisingly small amount of disk space to keep several months' worth of twice-a-day snapshots.
To set up Shadow copies, open up "Computer" and right-click the drive on which your data resides, choosing "Configure Shadow Copies". If you just select "Enable" on the resulting dialog, it will just use the defaults; store shadow copies on the same volume as the data itself with some default size limits. I much perfer highlighting the drive, then clicking "Settings" to choose a drive on which to keep the backups and configure max sizes (when you hit the limit, it starts deleting shadow copies, oldest first...so you've got kind of a moving window of times you can roll files back to). For several reasons, it's best to locate the shadow copies on a different drive than the data itself; performance is far better on separate (physical) drives, and also that way if the drive stops working, the shadow copies don't die along with the data itself.
Once the options are set, click OK to return to the Shadow Copies dialog, then "Enable" the shadow copies. It will take an initial snapshot right away, then proceed as scheduled from there on out.
(By the way, if you ever want to stop making new shadow copies but not erase the shadow copies you've already made, don't click the "Disable" button [which deletes all existing shadow copies] - instead just delete the scheduled task that captures the copies - the "Next Run Time" will change to "Disabled", but the shadow copies will still remain available for opening or restoring).
Easy, isn't it? And it's a GREAT tool!
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