In the modern life, the operation and the success in the operations of almost all businesses, institutions, organizations (hereinafter called as enterprises), depend a lot on information technology infrastructure (IT) accounts. In terms of IT, the basic core of the operation of businesses is the process of storing, processing and exchanging data and information. Related to this process, and also one of the most important components of the information infrastructure is the storage system, the concept of “storage systems” refers to the set of all resources used for data storage purposes of the system, including:
- Storage devices such as hard drives in server, external disk cabinets, tape devices
- Management software, drivers or provide additional features (such as replication, backup, ect …) for the storage device
- The protocol and accessories for connection and exchange of data between storage devices
To operate on the basis of enterprise smoothly and efficiently, the storage systems should be designed and operated under a high supervisor. And they should also be invested properly into the economic value as well as technology industry. All of the necessary data for the operation of the business must be adequately stored (which requires sufficient capacity), with safety and security, allowing access to high speed. It is used and processed efficiently and reasonably (requirements for performance and storage administrator).
To meet the requirements above, the storage technology sectors are having a rapid development roadmap with many new advances in technology to enhance the value and efficiency of storage systems. Monitoring research and practical implementation, we can see that the current trend of development of storage technology focuses on hot spots as follows:
- Use a separate storage network, for the purpose of high-speed data storage (SAN: Storage Area Network)
- Assigning the importance of data, based on which we can use suitable equipment and storage technologies, minimizing the cost of investment and operation. Storage principles which are consistent with the importance of the data can be applied as a fertilizer storage level (tiered-storage) and storage management under data lifecycle (ILM: Information Lifecycle Management).
- Conduct consolidated storage system under the virtualization method, improving efficiency.
In the next section, the article will introduce and analyze the technology directions above.
- The definition of SAN storage
- The benefits of SAN storage
- General features of SAN storage
- The other information related to SAN storage
The definition of SAN storage
Network storage can be understood as a method to access data on the network platform applications that process data on the same network as the data transfer from familiar devices on the server such as Disks Drivers like ATA or SCSI.
In a storage network area, a server uses a request for a specific packet or a specific data, from disk storage and the requirements satisfied. This method is known as block storage. The device works as a storage device within the server and is accessed via a normal way of specific requirements and processes to meet the requirements by sending and receiving the network environment that blow.
Traditionally, the method to access the file as NFS or SMB and CIFS, a server uses requests for files as part of the file system on the machine, and ordinary managed server. Process control which is determined from the physical layer of the data, access it as an internal drive in the server and is controlled and used directly on a server. The sole difference is that normal data is accessed via BUS systems; meanwhile SAN is based on the network platform. The network storage system uses the SCSI protocol to transfer data from the server to the storage device, not via the BUS system. Specifically, SAN physical layer is based on the optical port for data transmission: four Gbit Fiber Channels, two GBit Fiber Channels, one Gbit Fiber Channel and one Gbit iSCSI. SCSI protocol transmission information is transported on a low-based protocol layer mapping process. Most of current systems or SANs are using SCSI-based fiber optic systems for data transmission and the transition team (mapping layer) from SCSI over fiber and SCSI server is still understood as SCSI over Fiber Channel and FCP is considered as a benchmark in the transition there. ISCSI is a modified form of transmission which is similar to the method designed to bring the information SCSI over IP.
The benefits of SAN storage
It is easy for us to share storage and manage information and expand the range of storage via the process of adding storage devices. In addition, network has not need to change devices such as servers or current storage tools. Applications for the system and the Cluster Data center are being used. And each storage device in the network SAN storage is managed by a specific server. In the process of SAN management, using Network Attached Storage allows multiple computers to access the same file on a network. And today we may integrate SAN with NAS to create a complete information storage system.
SANs are designed to easily take advantage of the storage features that allows multiple servers to share a storage device.
Another application of the SAN is the ability for the computer to boot directly from the SAN which we manage. This provides easy replacement of faulty servers when in use and can be configured to allow changing or upgrading servers easily and the data is not affected when the server fails. And that process can be just half an hour to have a Data Centers system. Besides, it is designed for data transfer speeds and enormous safety system is considered as the top issue.
SAN storage offers data recovery solution quickly by adding storage devices which are capable of fast data recovery when a storage device fails or is not accessible (secondary array).
The current system allows new SAN (duplication) or a file copy to be recorded in two different physical areas (clone). That enables ultra-fast data recovery.
Furthermore, the disadvantages in terms of speed of performance are also repulsed in the next development step with the arrival of the technology setting up a separate storage network called as SAN.
The main advantage SAN brings to users:
- Increase the efficiency of performance: The performance of the storage system and the entire of IT system are significantly increased. In addition, the network transmission speed of SAN technology with the use of optical reaches 4Gbps speeds, reducing the time to access data in the course of use, backup, recovery. On the other hand, with separate SAN storage network, data traffic on the LAN protocols used conventional TCP/IP networks no longer needs to share lines with limited capacity data flow storage systems, backup. This separation individually optimizes operation of both LAN and SAN.
- Increase the flexibility of the storage system: SAN provides flexible storage system. The standard protocols and technologies used in the SAN network allow the use of multiple types of storage devices of different manufacturers, as they comply with industry standards. Network storage SAN can be used by multiple servers, many different applications. The storage capacity of the SAN network can be expanded and upgraded easily. Furthermore, SAN network opens up the possibility of storage resource consolidation, improving efficiency of storage systems and allowing operators and more efficient management.
- Reduce total cost of ownership: for those enterprises with more data, although the initial investment costs for the construction of SAN network can be much more expensive than the cost for building conventional storage systems; in the long run, SAN is the reasonable investor ownership costing (including operational, management, and storage) lowly. First, the user opens the SAN network management capabilities which are pliable, flexible, and simple, thus reducing the cost of management and administration. Second, SAN also supports many other convenient features during use (such as storage consolidation, supporting rapid data recovery after a disaster, a disaster …), increasing efficiency of the system. It is totally worthy with the initial investment costs.
General features of SAN storage
The basic characteristics:
- The storage is accessed via Block through SCSI
- Supply I/O ability with a high speed
- Separate the storage devices from servers
- Make it easy to share storage and manage information
- Expand storage easily by process of adding storage devices into network without change of tools such as servers or current storage devices.
- Allow many servers to share the same storage device
- Allow changing and upgrading a server easily and files are not be affected when the servers are in trouble.
Process of control for enterprise SAN environments with rapid development quickly demands for the satisfaction of all requirements of data transfer at high speed to the drive (as the data transmitted from the system of mail servers, server data, servers and file servers). In the previous development process, with the enterprise network using SCSI storage system and Raids, all hard disk arrays are integrated directly on the server. And now with technology IP-based networks, applications and data while being used up all of the storage on servers will end users to replace servers required to meet the job requirements. But upgrading the SAN storage device is very simple to add to the network of new storage devices.
The other information related to SAN storage
The types of SANs
SANs are built with specifically design for the storage and transmission of information. It provides the ability to transmit data at greater speeds and higher security protocols, such as NAS. Most of the SAN technology is the fiber-optic network (Fiber Channel Networking) together with the storage device using the local SCSI drive. One particular form of Fibre Channel SAN built by Fibre Channel Switch is connected to the device via optical cab system. Today most of SAN systems are using Fibre Channel routing solution, and bring greater scalability for SAN architecture allowing SAN systems to combine together. But most of those processes are for the purpose of centralized data and extremely high transmission speeds with greater distances through the fiber optic physical layer and the optical switch.
Another form of SAN is to use iSCSI protocol. It uses SCSI-based protocol TCP / IP. In this format, the Switches are similar with Ethernet switches. ISCSI standards were introduced in 2003 and implemented in the process vast network storage (storage does not require a great speed). And from the fiber optic applications during data transmission, it offers a great performance for iSCSI. Today most systems use optical fiber isSCSI during data transmission and NAS protocols such as CIFS and NFS.
SAN in the work environment
SAN is used in the environment that requires rapid expansion of storage devices, and meets job requirements (high-speed data transfer at large). It enables the FC disk device drivers to connect directly to the SAN. SAN is the same as the normal network storage device with large capacity. SAN solution is expensive with Fibre Channel systems or dedicated cards for computers. ISCSI SAN technology is the solution meeting the requirements of SAN prices, but not as the technology used for large enterprise data center networks. The client can use NAS protocols like CIFS or NFS. With the ability to remotely access and recover data quickly when the error occurred, it is the good response to Data Center solutions. ISCSI and the ability of the environment respond to applications that do not require the ability to meet highly. Moreover, FC SAN meets the most stringent requirements of the application.
SAN in applications these days
In the process of rapid development of enterprise data or small and medium sized organizations, they all require having a storage device with large capacity and high safety information and SAN is a solution that meets the requirements for the most demanding enterprises.
With data transfer speeds from 300 MBs to 4GBs, SAN will meet the applications’ demand to record and provide data for current needs and future.
With the striking advantages, SANs have become a very good solution for the storage of information for the enterprises or organizations. SAN allows remote connection to the network storage device such as Disks and Tape drivers. The storage devices on the network or the applications running on that server are shown on the device as a server (as locally attached devices).