Problem description:
Is the core technology, such as how to structure? What software do you want to use?
Analysis:
Digital library is a digital information resource system supported by modern high technology, and it is an information resource management mode on the next generation Internet, which will fundamentally change the current situation of information dispersion and inconvenient use on the Internet. Generally speaking, the digital library is a very large-scale knowledge center, which is not limited by time and space and is easy to use.
As an important carrier of knowledge economy, digital library is an important part of national information infrastructure, which has become an important symbol to measure a country's information basic level and one of the focuses of cultural and scientific competition among countries in this century. For our country, the research and development of digital library started late, so it is more necessary and urgent to build digital library.
Demand analysis of digital library
In terms of capacity, the demand of digital library for storage system is centralized data storage, which has the characteristics of high availability, expansibility and easy management.
In terms of content, the digital library integrates audio, video, multimedia and other forms of media resources, creates an unprecedented new reading space, and provides more audio-visual materials for teachers and students to use in teaching, which greatly enriches the service connotation of the digital library.
It is most suitable to store such rich media resources on optical fiber disk array, which can provide high continuous bandwidth and still provide high data transmission bandwidth under the condition of large user access.
The Construction Mode of Digital Library
The Great Wall suggests that libraries should build digital libraries in stages, which is based on the construction mode of digital libraries and the perspective of fully protecting the investment of colleges. If you use SCSI storage devices, there will be great problems in future expansion. This is because the scalability of SCSI devices is poor. If you need high performance, you have to sacrifice scalability. If high scalability is required, it will inevitably affect the performance of the equipment. However, the optical fiber storage device itself has a very high scalability, which increases the capacity and has little impact on the performance. Now it is considered that the SAN network structure with optical fiber storage equipment as the core can provide stronger expansion ability and more stable and efficient performance. This structure can be similar to the existing network, which can flexibly increase storage devices and hosts, and at the same time, with the continuous decline in the cost of optical fiber hard disks, it can save a lot of money for users.
Scheme Design of Great Wall Digital Library
1) Scheme design principles
? High availability
? high reliability
? High expansibility
? Fully protect users' investment.
2) Core technology and design
Great Wall Group has made a comprehensive consideration of the digital library system of the school from the actual needs of users. The whole system puts high availability first. In addition, it also takes into account the requirements of system performance, high scalability, openness, maintainability, simplicity of user operation and full protection of user investment.
In order to solve the access bottleneck caused by the storage mode of the server, Great Wall adopted the method of separating the information storage device from the server, and the network users can directly access the storage device through the network. This new network storage mode, which realizes direct access to storage devices through the network and regards storage devices as standard network devices, is SAN.
SAN is actually a storage device pool, that is, a subnet composed of disk arrays and optical fiber devices. Each system on the Ethernet main network can share the storage space on this subnet. It is the place where enterprises store data. Before being called by the server, all data resides on the SAN. Only when the server calls them will the SAN become a client network. It makes the storage system and the host independent of each other in physical connection and function, and forms their own networks, which realizes the leap from point-to-point access between the host and the disk array to many-to-many access. It uses high-speed Fibre Channel connection (FC-AL) to effectively improve the system performance when multiple servers are clustered.
SAN, as a new storage solution, each server is physically connected with all storage devices through Fibre Channel switches and hubs. It has the following advantages: it accelerates the speed of data transmission; Provide greater flexibility; The complexity of the network is reduced, and the influence of transmission bottleneck on the system is alleviated. In addition, this structure greatly improves the efficiency of remote disaster backup.
SAN-based storage device connection
3) Globality and integrity
In the scheme design, the Great Wall fully considers meeting the different equipment and functional requirements of digital libraries. Configure equipment according to functions and requirements, and implement centralized and unified management of equipment. When designing a digital library, we should consider the compatibility of existing equipment and the principle of integrity of library work.
4) Advanced and mature
On the basis of ensuring reliable operation of the system, the starting point should be high. Great Wall Group has selected the advanced equipment in the world, which makes the data processing, data storage and backup system have a high technical level to adapt to the future development.
5) Standardization and open compatibility
The computer system, storage system, network architecture and communication protocol used in the system are in strict accordance with international standards, which meet the requirements of network interconnection, safety and reliability, and have passed strict compatibility tests.
6) practicality and development
In the design, practicality and operability should be considered first, so as to fully meet the growing demand of digital library engineering data. In addition to meeting the current business needs, we should also consider the future business development needs, such as the opening of digital libraries to the society, charging operation, etc., in order to ensure the smooth upgrade on demand in the future, make full use of existing resources and protect investment.
7) System structure design
8) Advantages of the design scheme
? The network connection adopts SAN (Storage Area Network) architecture to ensure the high performance of the system. Storage devices can be added to the SAN network at will to improve the storage capacity of the system.
? The system adopts all-fiber disk array products to ensure the high performance of the system.
? The adopted disk array products are completely redundant in structure and hardware composition (such as array controller, two internal optical fiber loops, power supply, fan, link controller, dual-port optical fiber hard disk, etc.). ), and there is no single point of failure to ensure the safe operation of the whole system.
? Disk arrays can adopt different RAID protection levels to ensure the different needs of users.
? The storage system can provide high scalability, online capacity expansion and good investment protection.
? All hardware can support hot plug to ensure the continuity of system application.
? The system can be upgraded online without downtime.
? The system has good openness, and products from different manufacturers can be interconnected. The system supports a variety of host systems and cluster systems.
? The security of the system is very high, and data can be isolated or shared according to users' requirements.
? The redundant connection of physical paths can be supported by adding application software to improve the security of the system.
? Remote disaster tolerance function can be provided to prevent data loss caused by unexpected disasters.
? Storage products adopt a graphical management interface based on Windows, which is easy to maintain.