Global deduplication is based on a common deduplication database( DDB) that can be shared among multiple storage nodes. It allows data from multiple copies to be deduplicated against each other, eliminating redundant data between copies.
Global deduplication ensures that redundant data is not stored on multiple storage media. If a node detects that data has already been copied on another node, then the corresponding node does not create any additional copies of data.
In global deduplication, all backup copies are scanned for redundant data, which is then eliminated. The data set is stored on the deduplication database (DDB). This is extremely interesting for data centers because deduplicated data is usually stored on multiple storage media. Since the copies are deduplicated using the same DDB database, they are deduplicated against each other, eliminating any redundancy in data center backup.