Design And Implementation Of Dynamic Mirror System And Its Disaster Recovery Expansion

As the importance of information data in today’s society has become increasinglyprominent, the high availability and disaster tolerance capability of information systemis increasingly becoming the focus of attention. Balancing the data availability，accessing performance and the cost of building and maintenance are essential fordesigning disaster tolerance systems. Unfortunately, most users who use storage deviceswould not design a high-available and high-reliable system when they build the systemat first. Considering the cost, most users would choose to build a simple and smallstorage system at first. With the expansion of the business and the upgrading of theapplication, users have the requirement to build a storage system on the original systemwith higher-availability. It is unacceptable to build a new system which lead to theoutflow of some customers. How to ensure business continuity and improve systemavailability at the same time becomes a problem. So most users need to builddynamically loaded mirroring protection or dynamically loaded disaster toleranceprotection system at runtime.Existing mirror system can not be loaded dynamically and existing disastertolerance systems have some limitations such as dependence on specific storage devicesand/or low level drivers, poor performance and the original data migration to thedisaster tolerance system resulting in the long stagnation of the business when providingdisaster tolerance protection to local server with huge amount of data.To resolve these problems, we design a dynamic mirror system and apply it to astorage area network environment, combining with storage virtualization technology,put forward a dynamic disaster recovery architecture based on dynamic mirror system.First of all, this system can provide mirror protection and disaster toleranceprotection on the original storage architecture of local server. Second, ensure thecontinuity of the business as much as possible and build original system mirror andtolerant protection. Third, this system based on a software implementation, and does notrely on special equipment or other underlying driver. Finally, based on the dynamicmirroring disaster tolerance architecture ensure data consistency and produce a verysmall impact on the performance of the protection system by pull-log-basedasynchronous data transfer. The performance test data showed that, in the synchronousmode, the impact on the performance of the original system does not exceed20%andthe impact on the performance of the original system in the asynchronous mode doesnot exceed10%.