What is RAID and have some kind of RAID ?
In recent years the investment raid for desktop or mainframe systems is essential . In the few years before the raid may hear something called the luxury market , but compared to today's computing device and the data is lost , damaged hard drive is what people think of first is to use rAID for your system . The majority of today's motherboards have RAID technology that supports RAID Controller card slot plug but not everyone knows how to use effectively . I only article introduces basic information about RAID . How to configure , create raid array hard ... as well as software raid , then you search in google or forum or read more of the document .
A. So What is RAID ?
RAID stands for Redundant Array of Independent Disks . Initially , RAID is used as a protective solution because it allows you to burn data onto multiple hard disks simultaneously . Later , there were many variations RAID allows not only ensure data security but also significantly increase the speed of data retrieval from hard disk . Here are five common types of RAID are used :
1 . The RAID 0
This is a form of RAID is preferred by users the ability to enhance data exchange performance of the hard disk . Requires at least two hard disks , RAID 0 allows the computer to write data to them in a special mode called Striping . For example you have 8 data segments are numbered from 1 to 8 , the odd -numbered sections ( 1,3,5,7 ) will be written to the hard drive first and the even numbered sections ( 2,4,6 , 8 ) will be written to the second disk . To make things easier , you can imagine I have 100MB data and 100MB instead put on a single disk , RAID 0 will help put 50MB hard disk in each half to help reduce the working time according to the theory . From there you can easily figure out if there are 4 , 8 or more hard disks than the reaction rate will be higher . Still sounds appealing but in reality , RAID 0 is still hidden risk of data loss . The main reason lies in the way they divide and record information such as the data does not lie entirely in a hard disk and retrieved when needed information (eg a file ) , computers will have synthetic the hard disk . If a hard disk malfunction , the information ( files ) that can not be considered as read and lose . Fortunately, with modern technology , hardware products are quite durable so the cases of data loss occurs not so much . Maybe that RAID 0 is really suitable for users who need quick access to large data volumes , for example, gamers or those specializing in graphics , digital video .
2 . RAID 1
This is the most basic form of RAID capabilities ensure data safety . Like RAID 0 , RAID 1 requires at least two hard disks to work . Data is written to two identical disk ( Mirroring ) . In the case of a drive malfunction , the remaining drive will continue to operate normally. You can replace the broken drive without worrying about missing information problem . For RAID 1 , performance is not the leading factor that should not be surprising if it is not the number one choice for speed enthusiasts . However for network administrators , or those who have to manage multiple credentials , the RAID 1 system is indispensable . Ultimate capacity of the RAID 1 system with single disk size ( two 80GB drives running RAID 1 system will only see a 80GB RAID drives ) .
3 . RAID 0 +1
Have you ever wished an agile storage system such as RAID 0 , RAID 1 safe or not ? There is certainly evident desire and not just your own . Thus, the system combines RAID 0 +1 was born , synthetic advantages of both "elder " . However, the cost for a system of this type is quite expensive , you will need a minimum of 4 disk RAID 0 +1 hard to run . Data will be recorded simultaneously with 2 to 4 hard disk drives accelerated format Striping and Mirroring 2 format backup drive . 4 drives have identical when put into the system and RAID 0 +1 , the final amount will be equal to half the total capacity of 4 drives , for example, you run 4 80GB drive , the amount of data " that is " is ( 4 * 80 ) / 2 = 160GB .
4 . The RAID 5
This is perhaps the most powerful form of RAID for office users and families with 3 or 5 separate hard disk . And backup data is divided up all the hard drive . This principle is quite confusing . We return to the example of the data segment 8 ( 1-8 ) and is now 3 hard drives . Data segments 1 and 2 will be written to disk 1 and 2 separately , their backup piece is written to the hard drive 3 . Paragraph 3 and 4 are written to disk 1 and 3 with the corresponding backup segments written to disk 2 . paragraph 5 , 6 recorded to disk 2 and 3 , while the backup piece is written to disk 1 and then repeat this sequence , section 7.8 is written to disk 1 , 2 and written to disk backup paragraph 3 as the original . Thus ensuring RAID 5 improves speed , just keep high safety . The last hard drive space by using the total disk space minus one drive . That is, if you use the 80GB drive capacity 3 final will be 160GB .
5 . JBOD
JBOD ( Just a Bunch Of Disks ) is not actually a legitimate form of RAID , but it has some features related to a plurality of RAID and the RAID device driver support . JBOD allows you to attach as many drives as you want on your RAID controller ( of course within the limits allowed ports ) . Then they will be " integrated " into a larger hard drive for system use . For example, you plug it into the drive of 10GB , 20GB , 30GB through the RAID controller supports JBOD , the computer will recognize a 60GB drive . However, note that JBOD does not provide any other additional values : no improvement in performance , not provide solutions to secure data , just connect and synthetic capacity only.
6 . Several different types of RAID
In addition to the above mentioned , you can also encounter many different types of RAID , but they are not widely used , but is limited in the computer system to serve their own purposes , as can be told : Level 2 ( Error- Correcting Coding ) , Level 3 ( Bit - Interleaved Parity ) , Level 4 ( Dedicated Parity Drive ) , Level 6 ( Independent Data Disks with Double Parity ) , Level 10 ( Stripe of Mirrors , by contrast with RAID 0 +1 ) , Level 7 ( a trademark of storage Computer Corporation , allowing extra buffer for RAID 3 and 4 ) , RAID S ( inventor of EMC Corporation and is used in the system of their Symmetrix storage ) . Besides a number of other variations , such as Intel Matrix Storage RAID 0 allows to run with only 2 +1 or RAID hard drive on the system DFI 1.5 BMC 865 , 875 . Although we have many differences but are the most innovative methods of traditional RAID .
B. WHAT YOU NEED TO RUN RAID ?
To run the RAID , you need at least one controller card ( may be onboard or discrete graphics ) and two identical hard drives . Hard disks can be prepared in any way, from ATA , Serial ATA or SCSI , SAS best we should totally the same as a simple rule when operating in synchronous mode as RAID , the performance of the whole system will be pulled down low drive if available. For example, when you start running RAID 160GB drive with 40GB drive ( regardless of 0 or 1 ) , then you are deemed useless waste 120GB for control systems only regarded them as a pair only two 40GB hard drive ( except JBOD case as mentioned ) . The decisive factor to the number of drives that are RAID type you intend to run . Standard interface is not very important , especially between SATA and ATA . Some newer motherboards allow running RAID -style mixing both communicate with each other . MSI K8N Neo2 Typically Platinum or line nForce4 DFI LANPARTY . RAID controller ( RAID Controller ) is the focus of the data cable connecting the hard disk in the RAID system and it handles all data passing through it . The controller has several types , from detached to dense chip card integrated on motherboard . For PC systems , while not common but can choose to buy BMC integrated RAID is generally advisable because this is one of the solutions to improve system performance and most inexpensive clear , does not include value of their data safe . Another component of the RAID system is not required but is useful sometimes , it's the hot swap drive tray . It allows you to replace the hard disk malfunction while the system is operating without shutdown ( simply unlock , drawn out and plug the drive into the new drive ) . This device often used with SCSI or SAS hard drive and quite important for server systems which require continuous operation . The software is quite simple because most modern operating systems support RAID very well , especially Microsoft Windows . If you use Windows XP , the additional RAID 2k3 ... pretty easy . Most importantly, the great driver but when they were together with the equipment available .
After reading this article and you find that your system can run the config raid and did not know how they can read the following topic :
Compilation
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