Patent ID: 10402095

Abstract:
The system, devices, and methods disclosed herein relate to online data expansion in disaster recovery enabled data storage systems. We disclose embodiments that allow storage devices, which are coupled to one another in a disaster recovery, data replication-type scenario, to perform storage expansion in most cases without having to disable remote replication during the expansion. The teachings of this patent application facilitate methods of expansion for data storage device pairings where the data storage devices are the same size or where the primary storage device is smaller than the secondary storage device. In both of these situations, expansion occurs without disabling disaster recovery. In the situation where the secondary storage device is larger than the primary device, expansion is allowed, with the caveat that disaster recovery must be disabled briefly. Moreover, in situations where remote replication is lost or disabled, it is possible to expand a primary or secondary storage device independently, and then to enable expansion of whichever device was not expanded once remote replication is reactivated.