Distributed Storage Cluster Design for Remote Mirroring Based on Storage Area Network

With the explosion of information nowadays,applying data storage safety requirements has become a new challenge,especially in high data available cluster environments.With the emergence of Storage Area Networks(SANs), storage can be network-based and consolidated,and mass data movements via Fiber Channels(FCs)can be of very high speed.Based on these features,this paper introduces a dual-node storage cluster designed for remote mirroring as a concurrent data replication method to protect data during system failures.This design takes full advantage of a SAN system's benefits,and it adopts a synchronous protocol to guarantee a fully up-to-date data copy on the remote site.By developing a Linux kernel module to control the I/O flow and by using the technologies of software Logic Unit Number (LUN)masking,background online resynchronization and a self-management daemon,we have achieved a reliable mirroring system with the characteristics of server-free data replication,fault tolerance,online disaster recovery and high performance. In this study,we implemented the design in a remote mirror subsystem built on a software Fiber Channel Storage Area Network(FC-SAN)system.