Establish an efficient RAID system

 Construction of Internet cafes and efficient data exchange capacity RAID system to improve the English full name
RAID: Redundant Array of Independent Disks. Translated into Chinese and is the redundant array of independent disks, or simply disk array, from the University of California, developed in 1987. a long period of time, RAID server applications can only be seen in the high-end, with the technology, RAID disk array technology has been used in Internet cafes in this industry. At present, some large-scale bar on the hard disk capacity of a new data exchange requirements , especially the online theater, gaming applications such as data exchange server capacity requirements are very demanding, but also requires the disk array can be a long time cafe work, the cost can not be too high. Currently, RAID is not widely applied in Internet cafes, a number of technical staff The specific application of RAID is not mature. for Internet cafes, the performance in the end how to set up efficient RAID do?
cafes in order to form a highly efficient performance RAID, RAID works must be familiar with. RAID SCSI areas had previously been unique product because it was the technology and costs limit their low-end market. Today, with RAID technology continues to mature and the continuous efforts of manufacturers, Internet cafes have been able to enjoy relatively more low-cost IDE -RAID systems, although the stability and reliability can not be compared with the SCSI-RAID, but it is relative to the performance advantages of a single hard disk application of Internet cafes is a big temptation.
RAID works
RAID are designed mainly for large high-end servers and redundant data storage security. We can come to understand, RAID is a multi-block independent of the hard disk (physical disk) in different combinations to form a disk group (logical hard disk), thus providing more than a single disk storage performance and provide data redundancy technology. composed of different ways to become a disk array RAID level (RAID Levels). in the user looks like a disk group consisting of a hard drive, Users can partition it, format and so on. In short, the operation of the disk array with a single hard drive exactly the same. The difference is that the storage disk array is much higher performance than a single hard disk, and in many RAID mode has a more complete inter-school check / recovery measures, or even mirror each other back up directly, thus greatly improving the fault-tolerant RAID systems, improve the stability of the system redundancy, which is the origin of the word Redundant.
However, All the biggest advantages of RAID systems is from the remaining drives to reconstruct data without disruption server or system, you can automatically rebuild a failed disk data. this point, the user on the server, and other demanding users is crucial.
data redundancy function that is: the user data in the event of damage, the use of redundant information can be made to restore damaged data, thereby safeguarding the security of user data.
As RAID technology is an industry standard, Internet cafes to want to do RAID disk array, a practical need to understand all the major RAID levels on a general understanding to do.
RAID at all levels
RAID 0
RAID 0, also known as Stripe or Striping, with work set in the translated way. It represents the highest of all RAID levels of storage performance. RAID 0 storage performance increase is to the principle of continuous data access across multiple disks. The system transmitted to the data, after an average of RAID controllers are usually assigned to several disks, and all this is absolutely not for the intervention system, each disk belongs to its own implementation of that part of the data request. This system has a data request to multiple disks in parallel can be implemented. The data The parallel operation can take advantage of the bus bandwidth, significantly improving the overall disk access performance. We can simply think: N is a hard disk capacity of a hard disk capacity of N, and the work in order to obtain greater composed of logical disk drives (RADI 0 disk group) issued by the I / O request for data is converted to two operations, each of which corresponds to an operation a physical hard disk.
through the creation of RAID 0, the original sequence data request is distributed to all the two hard drives simultaneously. In theory, the parallel operation of two hard drives so that the disk read and write the same time 2 times faster. Although the bus bandwidth and other factors, the actual will certainly enhance the rate is lower than the theoretical value. However, a large number of parallel transmission and serial transmission of data comparing the effect is very obvious speed.
RAID 0 does not provide the biggest drawback is data redundancy, its security is greatly reduced, a disk array of any form of damage will be catastrophic data loss. For the bar that is not too harsh on the data requirements for the business premises, RAID 0 could meet the requirements.
RAID 1
RAID 1 also known as Mirror or Mirroring, translated into the mirror in the way. This work is entirely for the emergence of data security, because in the course of the entire image, only half of the disk capacity to be effective, because the other half is used to store This is exactly the same with half of the data, that is, the data redundant. Compared with RAID0, it is the other extreme. RAID0 primary consideration is the disk speed and capacity, ignoring safety; the primary consideration is the RAID1 data security , capacity can be halved, the speed can be the same. Its purpose is to ensure maximum user availability and recoverability of data. Therefore, RAID1 is not suitable for bar applications.
RAID 1 mode of operation is to write the user one hundred percent into the hard drive automatically copies data to another hard disk. When reading data, the system start with the source disk RAID 0 read data, read data if successful, the system never mind the data on the backup disk; if data failed to read the source disk, the system automatically switch to read the data on the backup disk will not cause interruption of the user tasks. Of course, we should promptly replace the damaged hard drive and backup data using the re-establishment Mirror, to avoid the backup disk In the event of damage, causing irreversible data loss. Because of the data stored in one hundred percent of the backups, at all levels of RAID, RAID 1 provides the highest data security. Similarly, one hundred percent of data backup, backup data of the total half the storage space, so, Mirror of disk space utilization is low, storage costs are higher.
Mirror, although not improve memory performance, but because of its high data security, making it particularly suitable for storage of important data, such as server and database storage and other fields. due to higher costs, the speed increase is not obvious, it is recommended not to use Internet cafes RAID 1.
RAID 0 +1
As its name RAID 0 +1 RAID 0 and RAID 1 is a combination of form, also known as RAID 10. It appears that in order to achieve both high speed and security purposes, RAID10 can simply be understood as two separate multi-disk RAID0 array consisting of the mirror again; in fact, wrong turn, did not understand.
composed of four disk RAID 0 +1 example, RAID 0 +1 storage performance and data security is a balanced program. It is the same as RAID 1 provides data security, but also provides a RAID 0 approximate storage performance.
as RAID 0 +1 is also 100% backed up by data to provide data security, so the disk RAID 0 +1 and RAID 1 the same space utilization, storage costs are high.
build RAID 0 +1 big investment cost of the array, data space utilization rate. not the kind of cost-effective RAID solutions. but especially suitable for both large amounts of data need to access data while on the field of safety-critical, such as banks, financial, commercial supermarkets, various government records management. for strict data security requirements of large Internet cafes, you can choose RAID0 +1.
for applications from Internet cafes, RAID0 to meet basic needs. cafes to build RAID required to purchase a dedicated RAID disk array card, use the IDE interface hard disk as Internet cafes, so buying RAID card, must purchase supports RAID IDE interface card. At present, some motherboard also comes with RAID card, but a limited number of hard drives supported. Internet cafes can be according to their actual needs, select the appropriate way to set up RAID.
Here, we feature integrated RAID motherboard, for example, talk about how to set up RAID disk arrays. Typically, the motherboard integrated RAID capabilities only supports SATA hard disk array, do not support the IDE hard disk array, in the procurement of hard disk, you should first look at the motherboard manual. Because RAID disk array set up at least a multiple of two or two hard drives, so we must pay attention when buying hard drives: the most good to buy the same capacity, same brand same model hard drive, so you can maximize investment protection, to avoid waste of resources.
Step one: Open BIOS of RAID functions. installed SATA hard disk, open the south to enter BIOS RAID function bridge chip. The specific method is: to enter BIOS setup utility Restart the computer. (Note: This example is based on the Intel ICH5R chip description)
Step two: set up RAID array. in the BIOS to start the RAID feature, ICH5R South Bridge chip, built-in ROM enter the Intel RAID Configuration Utility window. In the window, the window is the upper part of the main menu, the lower half shows the two hard drives already installed information, such as hard drive type, capacity, whether it has been set up RAID system. < br> to move the cursor to the main menu Enter the name of a RAID volume, you can usually use the default name; press the type of RAID 0 or RAID 1; according to their actual need to select RAID type (if you want to improve disk performance, select RAID 0; If you want better security, select RAID 1), press the Move the cursor to the car keys, a message appears asking to create RAID system to confirm.
Note: If you are creating this type of RAID 0 RAID system must be created before the backup data on the hard disk, or create a RAID 0 once system, all data on the hard disk and partitions will be deleted.
press create a RAID volume.
press : partition and install the operating system.
If you create a RAID system is a RAID 1, then the system will automatically back up data on the master disk to the slave disk, then if the primary disk operating system already installed, you can directly into Windows, as long as the access to Windows after installing Intel's ICH5R RAID driver can.
If you are creating a RAID 0, then the data on two hard drives will all be deleted, this time under the hard drive to re-DOS partition. partition method and the conventional hard disk partition is no different. partition is completed, install the operating system, Windows 2000/XP, etc. If you are installing NT core system, you must appear third party SCSI or RAID driverhh Windows2000/XP SATA controller driver to load as when.
hardware RAID card, RAID formation process is similar, in this narrative is no longer one by one, cafes and technical personnel can refer to the process of treatment.
In fact, RAID the formation is very simple, as long as clear RAID works, everything is very easy. cafes also according to their actual needs, the formation of efficient RAID, do not for the sake of fashion, engage in unnecessary investment.