Patent ID: 6499112
Filing Date: 2002-12-24
Classification: G06F

Abstract:
In a peer to peer remote copy (PPRC) system having a primary storage system including a plurality of storage volumes and a secondary storage system including a plurality of storage volumes, wherein storage volumes of the primary storage system correspond to respective storage volumes of the secondary storage system to form established PPRC storage volume pairs in which data written on primary storage volumes is automatically written on to the corresponding secondary storage volumes, wherein the storage volumes of the secondary storage system that are part of the established PPRC storage volume pairs are only accessible to receive the data written on to the corresponding primary storage volume, a method for making data available from established PPRC storage volumes of the secondary storage system, the method comprising:isolating the secondary storage system to be in a stand alone state such that access from any storage systems and hosts is prevented; determining if each storage volume of the secondary storage system is part of an established PPRC storage volume pair; terminating each established PPRC storage volume pair such that the storage volumes of the secondary storage system that are part of the established PPRC storage volume pairs are accessible to hosts; and making the secondary storage system available to storage systems and hosts to effect data recovery of the established PPRC storage volumes.