Patent ID: 6910098
Filing Date: 2005-06-21
Classification: G06F

Abstract:
1. A consistency group program for use in a data processing apparatus for maintaining consistency between first and second redundant data set copies wherein program; processed by a host interact with the first data set copy, wherein at least one of first and second redundant data set copies is stored on a plurality of separate magnetic disk storage systems and wherein data transfers to the second data set copy occur over multiple independent communication paths between said plurality of separate magnetic disk storage systems storing the redundant data set copies, said consistency group program comprising: A) a monitor module that determines, independently of and asynchronously to transfers between the host and the local storage facility, the efficacy of transfers from the first data set copy to the second data set copy over each independent communication path to the second data set copy, B) a suspend module that terminates all transfers from the first data set copy to the second data set copy over all the independent paths in response to a determination by said monitor module that a transfer over any one of the independent communications paths is not efficacious whereby the entirety of the second data set copy thereafter remains unchanged, operations between the host and the first data set copy continuing during the termination established by said termination means, and C) a resume module that reestablishes transfers to the second data set copy over all the independent communications paths after all communications paths are determined to be efficacious.