Patent ID: 9575676
Date: 2017-02-21
CPC Classifications: G06F

Claim:
1. A method for synchronizing a first unit of data stored in a primary storage system and a second unit of data stored in a backup storage system and corresponding to the first unit of data, the method comprising: transmitting, by the primary storage system, a random value to the backup storage system in a command to encode the random value using a first digest of a second unit of data stored by the backup storage system; deriving, by the backup storage system, a first encoded value using the first digest of the second unit of data and the random value, in response to the command; transmitting, by the backup storage system, the first encoded value to the primary storage system; deriving, by the primary storage system, a second encoded value using a second digest of a first unit of data stored by the primary storage system and the random value, the first unit of data corresponding to the second unit of data; comparing, by the primary storage system, the first encoded value and the second encoded value; sending, by the primary storage system, a copy of the first unit of data to the backup storage system, if the first encoded value and the second encoded value are not the same; and storing, by the backup storage system, the received copy.