Patent ID: 7281157
Filing Date: 2007-10-09
Classification: G06F,Y10S

Abstract:
1. In a data processing system including a host and at least one disk array storage device including a plurality of first logical devices for interacting with a first application and that constitute a consistency group and at least one second logical device for interacting in a first mode as a mirror for a corresponding one of the first logical devices in the consistency group, a method for enabling the shift of the second logical devices to the second mode in a consistent manner whereby each second logical device can interact with a second application with read and write capabilities, said method for shifting to the second mode comprising the steps of: A) generating a request data structure for each second logical device in the consistency group, B) preventing write operations to each of the first logical devices in the consistency group associated with the second logical devices identified in the request data structure, C) shifting each of the at least one identified second logical device in the consistency group to the second mode after said write prevention operation occurs, and D) enabling write operations to all the first logical devices in the consistency group upon completion of said shifting whereby interactions between the first application and all the first logical devices in the consistency group resume and whereby the second application can interact with the second logical devices in the consistency group.