US Patent 9460178 Synchronized storage system operation

Techniques and mechanisms described herein facilitate the performance of duplicate data block instruction identification. According to various embodiments, a data block update operation message may be received at a communications interface in a secondary storage node. The secondary storage node may be configured to store secondary data mirroring primary data stored on a primary storage node. The primary data and the secondary data may each include a respective plurality of data blocks. The data block update operation message may include a data block update instruction for updating a designated one of the plurality of secondary storage node data blocks. The data block update operation message may include a primary storage node data block sequence number designating an update operation status. When it is determined that the data block update instruction is not a duplicate, the data block update instruction may be performed.