METHODS AND APPARATUSES FOR PROVIDING COPIES OF STORED DATA FOR DISASTER RECOVERY AND OTHER USES

摘要

A disaster recovery technique for computer systems obtains backup copies of data by arranging recording devices like direct-access disk devices into copy pairs of primary and secondary devices. Management of the device copy pairs within a single system and across multiple systems is facilitated by constructing maps of device information that provide a cross-reference between I/0 subsystem device numbers and hardware addresses. Information structures are constructed from the maps and used to facilitate defining and managing groups of device copy pairs.