There are three mainstream network storage technologies: 1 Direct attached storage (DAS), network attached storage (NAS), and storage area network (SAN).
1、 Direct attached storage (DAS) is characterized by the stacking of hardware, the storage operation depends on the server, and there is no storage operating system. Special application environment!
1. Servers are geographically dispersed. 2. The storage system is directly connected to the application server. 3. Connect directly to memory. Obvious shortcomings! Therefore, the data processing and transmission capacity is low; When the server goes down, it will affect the stored data and make it unusable. So it is inevitable that this technology will be replaced.
2、 Network attached storage (NAS): it is directly connected to the network through the network interface and can be accessed. The storage device is similar to a dedicated file server, which provides file system functions and reduces the cost of the device. The hardware and software architecture of the system is optimized. With data as the center, the storage device is separated from the server, and its storage device is completely independent in function. Support multiple TCPIP network protocols.
Performance features! 1. Shared access at small file level. The management interface based on WB realizes the configuration of system resources and user configuration management. Advantages: storage supports plug and play, web-based management, and device installation, use and management are easier. Solve the problem of insufficient storage capacity. Disadvantages: poor performance.
3、 The storage area network San connects the disk array to the server through a private switch. The biggest feature of using block level storage is that the storage device is separated from Ethernet and becomes an independent storage area network SAN system structure.
Data transmission process protocol! FC SAN, IP SAN and ibsan! 1. FC SAN has obvious disadvantages: it is expensive and complex, and it needs to pay the personnel training cost of FC protocol. 2. IPSAN is based on IP network to realize data block level storage. The advantages are obvious: low equipment cost, simple configuration technology, and large capacity storage space can be shared and used. IP storage mainly refers to iSCSI. 3.IBSAN。 The design idea is to establish a single connection link between remote memory, network, server and other equipment through a set of central mechanism (IB infinite bandwidth switch), and the IB switch will command the traffic.
Advantages: the structure is designed very closely, which greatly improves the performance, reliability and effectiveness of the system, and can alleviate the data traffic congestion between various hardware devices. In practical application, how to choose according to the business object point, environmental requirements, performance requirements and price requirements of the system. There is no best technology, only the most appropriate application, and the boundary of any technology will become blurred sooner or later.