The Method Of Data Monitoring And Reomte Asynchronous Replaying In The Disaster Recovery System

Data backup and disaster tolerance is very important for pivotal systems. Disaster recovery systems are mostly based on NAS or SAN currently. NAS is only suitable for local storage. SAN covers the maximum distance, ranging from 10km to 100km, but it's too expensive for average users because of need the private network or fibre channel. With the development of Internet, backup technology based on the cheap and convenient Internet resources have come out. The traditional backup technologies based on Internet usually work in cool backup mode because of the bandwidth and stabilization restriction.This paper studies the method for constructing a real-time and distance-free backup system based on Internet and brings the methods of data monitoring and recurring data changes asynchronously. Moreover, to detect the error during backup timely, a method of error controling that can be used in remote backup system is presented.An asynchronous and distance-free backup system based on Linux is presented. The system works in the device driver layer in Linux Kernel, so it is transparent to user. This system monitors the writing operation of local server and encapsulates the information in a record, which is save in the storer, then, the writing operation is transmitted and submitted to the remote backup server asynchronously. This system can adapt to the status of network and can works on Internet.The current backup strategy could be classified in several aspects: complete backup and incremental backup; logical backup and physical backup; synchronous backup and asynchronous backup.Specifically, the contribution of the paper includes:1. Discusses the current domestic and international backup methods.2. Presents the methods of data monitoring. By monitoring the process of data production on local hosts, this method can get the status of data changes in local server in the order they happened. This method can be used in the...