Importance

Loading Importance Indicators...

Abstract

A remote data shadowing system provides storage based, real time disaster recovery capability. Record updates at a primary site cause write I/O operations in a storage subsystem therein. The write I/O operations are time stamped and the time, sequence, and physical locations of the record updates are collected in a primary data mover. The primary data mover groups sets of the record updates and associated control information based upon a predetermined time interval, the primary data mover appending a prefix header to the record updates thereby forming self describing record sets. The self describing record sets are transmitted to a remote secondary site wherein consistency groups are formed such that the record updates are ordered so that the record updates can be shadowed in an order consistent with the order the record updates cause write I/O operations at the primary site. The secondary site optimizes the record updates of each consistency group such that record updates to a same target track are included in a single I/O CCW chain. Additionally, the record updates are written according to full consistency group recovery rules such that should the primary site be unavailable, the secondary site can recover a consistency group.

Loading the Abstract Image...

First Claim