Data storage Management ABC

The field of computing has changed a lot over the past 20 years, but the importance of computer processing and data generation has not changed, and when data is lost, all computing power becomes worthless. As the planners and builders of informatization, it must be seen that data is gradually becoming an entity that is stored and does not belong to any particular system, like capital or intellectual property, and that data is a shared asset that needs to be stored and protected. This is precisely the purpose and significance of data storage and management, is the content of this article, but also the value of the wave storage to customers.

Three ways to store data

There are three ways in which information can be stored in the form of data in storage devices, online, near-line, and offline. Online storage is the data stored in the host's file system directly managed by the disk storage device, which is characterized by the use of the bottom of the system I/O technology, the advantage of real-time access and change the data, excellent performance, to meet the application of the I/O performance requirements. Near-line storage refers to storing data in a disk storage device directly managed by another host's file system, this method usually uses a certain software and network to realize the data storage between different systems, as well as the data fetch when needed, the advantage is that the data is also stored on the system that is being put into operation. It can guarantee the transmission performance of data storage and fetch. Offline storage refers to the system running, the data stored in the system can be separated from the tape device at any time, its biggest feature is the use of tape technology, the advantage is that the system can get a copy of the data from the system when running, easy to store in the off-site. The combined application of these three ways will bring the user a perfect data storage and management scheme.

Store First, Post manage

The core purpose of informatization is to make use of information technology to provide better ways of production and service and to improve the competitiveness of the organization. A complete information system, usually composed of several subsystems, such as OA, Email, Proxy, DNS, DHCP, and various application subsystems and so on. All kinds of systems can operate 7x24, this is the basic requirements of information, in order to achieve this requirement, must have a perfect data online storage solution. Considering each subsystem globally and designing a unified data online storage system for the whole network system, it can simplify management, reduce investment and lay a foundation for data management. The data management plan is the safeguard measure of the system vitality, and it is also the basic measure to make the data reuse, to exert the data increment ability and to strengthen the competitiveness. Therefore, the design of a sound data management program, must first design a perfect data online storage program. http://bianceng.cn (Programming Entry Network)

With the development of storage technology, there are three trends in storage: independence, centralization and networking. The SCSI technology realizes the storage independence, makes the storage from the host system independent, becomes the independent equipment. Fibre channel Technology, the emergence of FC switches, HBA cards and FC disk arrays, allowing users independent of the enterprise local area network, in the background of the information Center, design a unified data online storage system, that is, storage area network (Fc-san). The recent advent of iSCSI technology has become a powerful competition for Fibre Channel technology, allowing users to build data transmission systems and storage systems (Ip-san) on the same Ethernet network. In the information planning, the most suitable one can be selected from these three technologies to form the data online storage system.

Data online storage is ultimately a pattern problem. Regardless of how storage technology is evolving, the storage model is not always able to escape from Das, NAS, San Three, where Das, san mode is stored in "block mode", NAS is on the Ethernet network, in "file mode" for data storage. No matter how big the application system difference, its data reads and writes the way to have two kinds: block way, File way. In general, all kinds of database applications, such as ERP, MIS, his, DM, KM, CRM and so on, all need "block mode" to ensure the performance of the database, and various multimedia data applications, such as digital files, digital pictures, digital video, digital audio and other data, as well as email, FTP, Web, The data of network application such as E-game, is stored and utilized in the form of file, can choose "Block storage" or "file storage" mode according to system scale and concurrent request number to the system performance requirement. Grasp the data processing method of the system, it is clear how the data is produced and how it is stored and utilized, and then considering the requirements of each subsystem in storage performance, capacity, expansibility, usability and manageability, the appropriate storage mode can be designed for each subsystem to solve the data storage problem.

Data management, on-demand customization

Data management differs from storage management, storage management object is storage space (or storage resources), its main content is storage device state monitoring, storage space online dynamic expansion and adjustment, storage space unified management and distribution, the purpose is to provide a stable and reliable storage space for the host and its applications. The data management object is the data in the online storage system, its management content mainly includes: obtains the data copy by various means to realize various level data security and the high availability characteristic, migrates the data in the different storage device, manages the data content. Storage management is targeted at online storage systems, while data management uses more data near-line storage and offline storage.

To design a data management plan, you must first have a clear purpose. The purpose of data management is to ensure the sustainable life of the system, improve the utilization of storage resources (or save the storage cost), data sharing or reuse (and hence benefit increment). Data management is attached to an online storage system, so when designing a data management scheme, you must consider the mode of an online storage system. After defining the storage mode and data management purposes, it is possible to choose appropriate means to achieve the ideal data management in various data management means, such as high availability cluster, backup, replication, disaster recovery, migration, content management, etc.

High-availability clusters, which are stored on the same data in the disk array, connect 2 or more identical hosts, through special software, make a number of hosts external virtual as an application system, internal can be distributed between multiple hosts load balancing, or designated host and standby system, in the main system downtime, The standby system takes over the application and ensures that the application continues to operate, thus enabling the application of highly available technology. High-availability clusters can effectively guarantee system sustainability, especially for relational databases such as SQL, Oracle, Sybase, Informix, Mysql, and dbii applications.

Backup refers to the form of a copy of the data in a certain way in order to recover the data if the source data is compromised. Backups have both near-line and offline backups, and the main difference is whether the backup device is a disk device or a tape device. Depending on the size and different storage modes, backups include stand-alone backup, network backup, Sever free, and LAN free Backup, among other ways. In comparison, a stand-alone backup is only suitable for a single application system, multiple application systems under the same network, suitable for network backup, and in the case of SAN storage mode, the Server free and LAN free are more efficient.