Detailed analysis of storage device type and storage system network architecture

Storage device type and storage system network architecture

Many beginners often ask the question: What is the difference between SAN and NAS, ISCSI storage? Which is better for SAN and NAS devices? "How do I choose a storage device for an application?

In fact, SAN, NAS, DAS, FC, ISCSI, FC-SAN, IP-SAN, etc. are not the same category concept. SCSI, FC, NAS, ISCSI and other concepts refer to storage device types. DAS, NAS, SAN, etc. refer to the network architecture of the storage system. The mainstream storage system network architecture that is often mentioned is DAS, NAS, and SAN. Among the SAN network environments, FC-SAN (using Fibre Channel storage products) and IP-SAN (using ISCSI storage devices) can be classified according to the types of storage devices.

Storage device type introduction

The storage device type refers to a storage device that uses interface types such as SCSI, FC, TCP/IP, ISCSI, data transfer protocols, and different data storage media. Common storage device types are SCSI storage, NAS storage, FC storage, iSCSI storage, and tape storage.

The core of the concept of storage device type is the device, which refers to a whole consisting of storage media, drives, controllers, power supply systems, cooling systems, and so on. It is independent of network layer devices and host layer devices, so when referring to storage device types, do not involve network devices and hosts connected to storage devices.

The externally provided interface of the storage device is FC Fibre Channel, and the storage device that transmits data according to the FC Fibre Channel protocol is FC storage. The storage medium is a FC disk storage called FC-FC storage. The storage medium is a storage of SATA disks and is called FC-SATA storage.

NAS is a special type of storage device. Although the NAS provides an external IP interface and performs data transmission according to the IP protocol, the NAS finally provides a file system to the host. SCSI storage, FC storage, and ISCSI are provided to the host. A bare, logical file volume without a file system, and the NAS itself is a server + storage structure, so strictly speaking, NAS should be a storage system structure, not a storage type. However, many times we regard the NAS server + storage structure as a whole, which in turn uses the standard IP transport protocol for access and data transfer. Therefore, NAS is generally considered to be a type of storage device. NAS is both a storage device type and a storage system network structure.

The storage device type refers to the classification of the storage device. The network structure of the storage system naturally refers to the overall topology formed by the storage device, the host, and the connection system between the storage device and the host.

Storage System Network Architecture Introduction

The storage system network architecture refers to the connection mode between the storage device and the host that needs to perform data read and write operations, such as the network topology, data read/write mode, storage sharing mode, and data sharing mode. The storage system has a different network structure, and the storage device works differently, in a different way. The mainstream storage system network architecture that is often mentioned is DAS, NAS, and SAN. Among the SAN network environments, FC-SAN (using Fibre Channel storage products) and IP-SAN (using ISCSI storage devices) can be classified according to the types of storage devices.

DAS (DirectAttachedStorage) direct-attached storage, topology map:

NAS (NetworkAttachedStorage) network attached storage, topology map:

SAN (StorageAreaNetwork) storage network, topology map:

Comparison of DAS, NAS, SAN storage systems

Note: Since the NAS itself uses files as the transmission unit and the database is the data block as the transmission unit. On large databases, if you want to achieve high performance, it is not recommended to use NAS products.

At present, SAN storage systems are the most widely used. In a SAN network environment, FC-SAN (using Fibre Channel storage products) and IP-SAN (using ISCSI storage devices) can be classified into storage systems depending on the type of storage devices. Design is a priority.

Ring And Fork Type Insulated Terminals

Ring And Fork Type Insulated Terminals,High quality insulated terminal,copper tube terminal

Taixing Longyi Terminals Co.,Ltd. , https://www.lycopperterminals.com