The E-government Virtual Desktop Cloud Storage System Based On CDMI

Desktop virtualization refers to virtualize the terminal system of computer(also known as virtual desktop). In order to achieve the safety and flexibility of the desktop, all of the desktop virtual machine are placed in the data center for unified management. Many large enterprises and government departments in favor of the desktop virtualization, because of its lower cost, convenient for centralized management, better data security and higher resource utilization. Companies and government departments for the large-scale deployment of desktop virtualization system, put forward new requirements and challenges for desktop virtualization of storage. How to manage and maintain the data center is an important problem to be solved.In view of the above problem, this article take the internship company research and development project which is the regional e-government cloud storage system as the background, according to the e-government virtual desktop's running environment and user data storage requirements, research on cloud data management interface, load balancing, snapshot and other related technology, on this basis, design and implementation a cloud storage system that many government departments can be shared.In this paper, the main work is as follows:(1)According to the data characteristics of the virtual desktop, this paper proposed an object model of virtual desktop which is based on the definition about object in CDMI standard. According to the virtual desktop files, the model defines five different objects. The data objects describe metadata of files, the container objects describe the folder properties, the domain objects manage file access permissions, the queue objects manage client multiple file operation instruction, the capability objects describe the function of file which has been de-veloped in system. Using MongoDB to storage object.(2)For the safe storage of the virtual desktop, this paper implemented a multi-replica document management mechanism. This mechanism stores three replicas for each virtual desktop file. Replica's storage location selection based on minimum weighted algorithm; the operation of replica include file read and write as well as data objects management, divided into asynchronous mode and synchronous mode. Synchronization refers to the client to complete three replica update in a single write operation on the file; the asynchronous means the client to complete only one replica update in a single write operation on the file, and the other two replicas' update are completed after the response operation.(3)In view of the virtual desktop fault recovery, this paper implemented the snapshot mechanism of the cloud storage system. The mechanism holds the state of the virtual desktop at some point, in order to recover to a specific point in time when the virtual desktop meet fault. Considering the demand of the virtual machine, need to lock the source object, in order to avoid virtual machine instances are destroyed; use of copy on write technology on the snapshot volume changes, and the source does not make any changes; Finally the bitmap is used to determine the location of actual copy of data, and determined from the source or the target to obtain data.(4)In view of the system in the operation process of all kinds of mistakes, this paper implemented the monitoring mechanism of the system. The administrator based on the comparison of different period of monitoring data, fast positioning system error by abnormal data, and timely giving the solution.Finally, in this paper, the function test and performance test of the cloud storage system is proposed, the test results show that the system is feasible and effective.