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Pretty much every storage vendor supports the concept of snapshots. Often these storage snapshots arc presented to companies by the vendor as a way to take SQL Server backups without having to worry about eating up large amounts of space. Some companies will even use this instead of tape backups. Because of the way these snapshots work, they don't make reliable backups.
Remember for a moment what causes a large majority of database corruption. It's a problem with the storage, in which the storage either incorrectly writes a block to the disk or a physical disk fails, causing the data to be lost. Snapshots use a technique called "copy on first write," in which, as blocks are written to for the first time by the disk array, the original block is copied to another location to be stored as part...