US Patent 10108819 Cross-datacenter extension of grid encoded data storage systems

Techniques for extending a grid encoded data storage system to additional datacenters are described herein. A grid of shards with a first index and a second index is created and a set of null shards is added to the grid of shards. When a data object is received for storage in the grid of shards, a set of shards with the same first index is selected for the storage location with at least one null shard and one or more other shards. The null shard is enabled for data storage by allocating a storage device for the null shard. The grid is then updated by storing at least a portion of the data object in the set of shards, updating derived shards in the set of shards, and updating derived shards with the same second index as the updated shards.