Education informationization After the construction of the “School-to-School, Banbantong” project during the fifteenth period, it entered the mature stage of market procurement in 2007, and users pay more attention to how to play the campus. Thoughts on investing in efficiency and implementing teaching applications. The education authorities also found that some schools often fail to keep up with the application of the network system, causing the phenomenon of idle equipment. School informationization leaders and network administrators have begun to consider application issues more and become more rational in terms of capital investment, system construction and procurement standards. Although the hardware procurement market in the education industry is still active in 2006, education informatization has entered a critical period of application transformation. The education industry users have fundamentally changed the guiding ideology of server procurement. From the initial procurement mode of “in-one purchase, top-level configuration” to the analysis of application requirements, the server configuration upgrade and rational funding distribution.
For the three application platforms in the construction of educational information application system: teaching platform, management platform and information platform, the role of servers in the three platforms is not in doubt. Server procurement should also be rationally upgraded and targeted for purchase based on the construction phase and development goals of the application platform. But no matter which kind of platform configuration, the server configuration should be analyzed from the most basic three elements of the server itself:
• Reliability:
The reliability of the server will be the quality of its products. The basic element, in fact, is also the primary consideration when purchasing a server. As the core of the campus network system, the server needs to have high reliability, and extend the MTBF (Time Between Failure) as much as possible to maximize the benefits of education informationization. Reliability is also a feature that remains reliable and consistent, including data integrity and warning actions for hardware failures before they occur. Redundant power supplies, predictable hard drive and fan failures, and RAID (Redundant Array of Independent Disks) systems are examples of common reliability.
• High Availability:
The development of campus network technology has further promoted the demand for servers. As the bandwidth of the school's backbone network is upgraded, the amount of data owned by users is also The speed of doubling every year, relying on the education and teaching applications carried by the server, also requires the server to provide uninterrupted system services. High availability is a feature that is always available and ready to use. It can refer to both the system itself and the ability of users to access their desired content in real time. Another major aspect of high availability is the ability to recover quickly from system failures. High availability systems may or may not use redundant components, but they should have the ability to run critical hot-swappable components. Hot swap is the ability to replace a failed component with a new component while the power supply is still on and the system is in normal operation. A typical example of high availability is detecting potential failures and transparently redirecting or switching faulty procedures to other regions or systems. For example, some SCSI device research automatically transfers data from hard-to-read sectors to spare sectors, and neither the operating system nor the user is aware of this change.
• Scalability
Scalability refers to the ability to increase server capacity (within a reasonable range). Regardless of the initial capacity of the server, you can rest assured that you can quickly increase capacity. I once built a video on demand platform, but because the school teachers and foreign teachers provided a lot of video resources, the storage space of the server reached saturation in 3 months. Fortunately, when the server was selected, the hard disk expansion was fully realized. Considering the rapid expansion of 4 hard drives to meet the needs of teachers. Here, I also remind you not to be greedy for a short time, and forget this principle, resulting in serious waste of funds. For the experience of campus network server management, we can specifically expand the scalability into the following factors, such as: * increase the processor's ability; * increase the memory capacity; * increase the capacity of the disk; * operating system restrictions etc. Mind
server product for an application to run on its, but differ vastly different configuration of the server itself, the type of application is also all-inclusive, we can mention the teaching according to the above in the actual selection process The application features of the platform, management platform, and information platform are used to select servers and determine their configuration to avoid wasting resources.
Server selection for supporting teaching platform:
With the improvement of network infrastructure, the wide application of computer and network technology, the increase of Internet users and the expansion of Internet access, network teaching has developed rapidly in recent years. In terms of distance education, online teaching has developed rapidly due to strong demand; the implementation of online teaching in schools has gradually gained wide application. As a teaching method widely used in primary and secondary schools, network teaching makes full use of the latest computer technology, network technology, multimedia technology, etc., so that teaching can span time and space constraints, with great flexibility and interaction. Sex, online teaching makes the display of teaching materials more flexible, vivid and vivid. It is the most powerful tool to support students' self-directed learning under the guidance of new teachers. Most of the online teaching content established by the school appears in the site as a courseware of the web page, and the user realizes the online teaching by accessing the courseware page in the site. In the overall structure, the B/S structure is adopted. The resources of various teaching pages are on the server side, and the central database is used to store and organize.
1. WEB and database server
WEB server Respond to the WEB request and run the relevant application. The performance of the server is determined by the content of the website. If the web site is static, the system bottleneck is: network, memory, CPU. If the WEB server mainly performs intensive computing (for example, dynamically generating web pages using the asp language), the system bottlenecks are: memory, CPU, disk, and network. Because these sites use the dynamic content of the connection database to generate transactions and queries, this requires additional CPU resources and enough memory to cache and process dynamic pages. Network bandwidth is also important due to high click-through rates and large amounts of dynamic data. If you support a Web service system and a database system on a server, you must consider the CPU frequency and memory capacity. The database server has relatively high requirements on the processor's main frequency, number, and cache. Depending on the specific application scale, four or more processors are generally used, and at least two processors are required. The larger the memory, the better. Large memory can even load the entire database to improve performance. Among the low-end servers launched by various vendors, if you want to choose a suitable database server, it may be the most difficult problem in our procurement process.
Second, the video-on-demand server
in distance learning has been recognized by the majority of educational institutions as an effective complement to traditional teaching, but, distance learning platform early is no longer a tertiary patent Conditional primary and secondary schools have also begun trials of distance learning. The professional video server is the core device of the entire distance learning platform system. It is responsible for media control and media stream transmission on the network. Its architecture determines the overall performance of the system. The main requirements for professional video servers are output capabilities and open architecture. The output capability is usually measured by the number of concurrent video streams. The key is the processing power of the CPU and the throughput of the system IO. This parameter directly limits the overall service capability of the system. Conditional schools can use the form of professional video server + disk array. If there is higher performance requirement, video cluster and load balancer can be used to open video resources to the external network. Schools with shortage of funds can purchase video server configuration solutions for primary and secondary schools provided by some manufacturers. This solves the financial problems and has also made initial attempts in distance education, adding more for the lack of school classroom effectiveness. power.
Server selection for supporting management platform:
Servers supporting management platform can be subdivided into two types: the first is a server that supports educational management, such as teacher information, student registration system. (CMIS), etc.; the other is a server that supports network services and user authentication management. Considering that the application framework of the first type of server is the same as the server supporting the teaching platform, the configuration requirements can be appropriately reduced according to the configuration mentioned above in terms of selection. The latter server selection for providing network services is more diverse. Here we cite two typical cases:
a "domain" domain controller is a controller
network management center users, computers, providing secure network environment. The primary domain controller not only responds to the user's login requirements, but also synchronizes and backs up user accounts, WINS, and DHCP databases between servers. In addition, the primary domain controller also performs DNS services. In a network that provides a "domain" management model, everyone may make a mistake and always think that a configuration with high performance is not. If the number of users is between 300-400, the average low-end server is fully satisfactory. For example, if the memory is configured, in addition to the memory occupied by the operating system, each additional user only needs to add 1 KB of memory for storing user accounts.
Second, gateway-based server
gateway-based server provides most user authentication and network access proxy function, using 1-processor server can. This type of server requires a high speed Ethernet card and at least a dual network card. For servers with proxy caching, hard disk speed is the preferred factor (you need to download web pages or files to the hard disk in advance), and efficient disk performance can ensure that the network speed of the client is not affected. Server selection for supporting information platform:
The campus network information platform is mainly for information communication and workflow management, and provides free sharing of file information. We have explained the most basic file sharing service provided by the campus network. The file server acts as a data storage repository for the network, and its performance requirements are to quickly transfer data between users on the network and the server disk subsystem. The main factors affecting system performance are the speed of the disk and the network subsystem. Memory as a buffer for transferring data also has a large impact on system performance. After adopting DMA technology, CPU utilization will be very low, and generally will not become a system bottleneck, and the stability and security of the disk is the focus of our consideration.
The advanced campus network service platform has not considered the data protection capabilities of the server itself. Because many departments at various levels, especially universities, have their own IT systems, running their own servers, many Data is also kept in this department, and the way of data backup is also different. The loss of teaching data caused by system failure will have a major impact on teaching applications. This kind of data decentralized management requires a large amount of manpower, material resources and financial resources as support. From the perspective of total cost of ownership (TCO), the post-maintenance cost of decentralized management is very high. Relatively speaking, after the teaching data is concentrated, the data can not only be well managed and maintained, but also the cost required is much reduced. Therefore, to get rid of the storage structure of a single server, the establishment of a distributed storage teaching data center concentration will become a trend of campus network development.
Finally, the Special noted that, because the primary and secondary schools network managers and system administrators to manage servers for uneven level, and as a server technology development, and gradually move toward intelligent low-end servers It is also bound to become a direction for the development of today's servers. When choosing a server, we should consider the above points and weigh the server intelligent management and the repair service provided by the manufacturer.