Redundant Array of Independent Disks (RAID) Technology PDF
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Exam 212-82, Data Security, covers Redundant Array of Independent Disks (RAID) Technology. This document details the method of combining multiple hard drives for fault tolerance and improved system performance. It explains various RAID levels, storage techniques, and their features, such as fault tolerance and performance.
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Certified Cybersecurity Technician Exam 212-82 Data Security Redundant Array Of Independent...
Certified Cybersecurity Technician Exam 212-82 Data Security Redundant Array Of Independent Disks (RAID) Technology A method of combining multiple hard drives into a single unit and writing O 0 1 data across several disk drives, offering fault tolerance (if one drive fails, the system can continue operating) Placing data on RAID disks enables a balanced overlap of input/output (1/0) operations, improving system performance, simplifying storage management, and protecting against data loss 0 3 RAID represents a portion of computer storage that can divide and replicate data among several drives by working as secondary storage RAID has six levels: RAID 0, RAID 1, RAID 3, RAID 5, RAID 10, and RAID 04 50, to function effectively. All RAID levels depend on the following storage techniques: Striping [—) Parity m Mirroring Redundant Array Of Independent Disks (RAID) Technology Many organizations depend on RAID technology for handling their critical backup needs, especially with the increase in data flow and data volume. Organizations are expanding their networks to improve their productivity. However, this additional increase can cause network bottlenecks. The probability of losing data because of disaster, threats, mistakes, and hardware failures hamper an organization’s ability to grow. RAID technology overcomes these situations providing an option for data availability, high performance, efficient and accessible recovery options without a loss of data. Understanding RAID Technology RAID technology is used to store data in different places on several disks. Storing the data on multiple disks improves the performance of 1/O I/O operations. RAID technology functions by implementing multiple hard disks as a single logical disk. It allows a more balanced storage of the same data across an array of disks. An effective implementation of this technology helps address the complex issues in fault tolerance. The data organized in RAID levels depends on the RAID storage techniques and installation methods. Usually, the implementation of RAID is done on a server. Although personal computers do not necessarily need this technology, they can still setup and utilize it in a smaller environment than an enterprise. RAID has six levels for functioning effectively: RAID 0, RAID 1, RAID 3, RAID 5, RAID 10, and RAID 50. Each level has the following features: = Fault tolerance: Even if a disk fails to work, other disks will continue to function normally. = Performance: RAID achieves high performance during read and write processes across multiple disks. Module 15 Page 1856 Certified Cybersecurity Technician Copyright © by EG-Council EG-Bouncil All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Data Security * Competence: This is defined by the amount of data stored. The storage capacity of disks depends on the chosen RAID level. The storage capacity need not be equal the size of the individual RAID disks. All the RAID levels depend on the storage techniques listed below: = Striping: Striping divides the data into multiple blocks. These blocks are further written across the RAID system. Striping improves the data storage performance. = Mirroring: Data mirroring makes image copies of the data and simultaneously stores this data across the RAID. This affects fault tolerance and data performance. = Parity: Parity uses a striping method to calculate the parity function of a data block. During a drive failure, the parity recalculates the function using a checksum method. Module 15 Page 1857 Certified Cybersecurity Technician Copyright © by EG-Council All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Data Security Advantages/Disadvantages of RAID Systems o°.*. RAID offers hot-swapping or hot plugging, that * RAID is not compatible with some hardware is, system component replacement (in case a components and software systems, for drive fails) without affecting network example, system imaging programs functionality “* RAID data is lost if important drives fail one RAID supports disk striping, resulting in an :! after another, for example, RAID 5, where a improved read/write performance as the 5 drive used exclusively for parity cannot recreate system completely utilizes the processor speed the first drive if a second drive fails too — Increased RAID parity check prevents a system : ¢ RAID cannot protect the data and offer a crash or data loss performance boost for all applications S — [S Advantages/Disadvantages of RAID Systems Before RAID technology was introduced, many organizations used a single drive to store data. RAID technology is now found across all storage devices in an organization. Advantages and disadvantages RAID depend on the implemented level. Advantages of RAID Systems Performance and reliability: RAID technology increases the read/write performance of the data on disks. The speed is much faster than when using a single drive as storage. It improves the performance by distributing the 1/0. A RAID controller distributes data over several physical drives, ensuring that a single drive in the RAID system is not overburdened. RAID sustains the reliability of data even if a disk fails. Failed components can be replaced in a RAID system without shutting the system down. This feature is called hot swapping or hot plugging. The replacement process does not affect the network or how the other disks function. Parity check: Parity check is a process where the RAID system compares the data stored in a crashed system with the data stored in other disks. This check process is accomplished on all drives. The parity check is performed after mirroring the data. Regular parity checks detect the probability of a system crash, thereby preventing data loss. Data redundancy: A disk can fail anytime. Therefore, data redundancy is important for an organization. RAID provides enhanced data redundancy in case of a hardware failure. Disk striping: Disk striping improves the read/write performance of data. The data is divided into small chunks and spread over multiple disks. Depending on the Module 15 Page 1858 Certified Cybersecurity Technician Copyright © by EG-Gouncil All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Data Security implemented RAID level, the data is divided into bytes, bits, or blocks. Data reading and writing can be done simultaneously on a RAID system. System uptime: This metric detects the reliability and stability of a computer. System uptime defines the time till which a system can be left unattended without any assistance. Configuring RAID on a system helps enhance system uptime. A high system uptime in an organization signifies a high productivity. Disadvantages of RAID Systems Writing network drivers: RAID technology is designed to be widely used on servers. A major disadvantage of RAID technology is the writing of all network drivers. RAID technology is complex, and this process can be time consuming. Non compatibility: Different systems support different types of RAID drives. Certain hardware or software components may not be compatible with the RAID drive configured on a server. This non compatibility may lead to the RAID not functioning properly. The compatibility between RAID drives, hardware, and software must be checked prior to configuring a system. RAID can protect data for all applications available on the network. For example, RAID is not compatible with system imaging programs. Loss of data: All RAID drives function in the same environment. They can become nonfunctional because of mechanical issues. Thus, the potential data loss increases if the disks fail one after another. When two drives fail at the same time, recovering the data from the disk becomes difficult. For example, RAID 5, where a drive used exclusively for parity cannot recreate the first drive if a second drive fails too. Time consumed in rebuilding: The increase in drive capacity has been much more than the increase in transfer speed. Recovering data from drives with a large storage capacity can be time consuming. In such scenarios, rebuilding a failed disk can also be time consuming. Increasing the number of drives does not help increase the data transfer speed. Cost: Implementation of RAID technology can be costly. Organizations need to hire consultants to sustain its performance. It also requires external RAID controllers and hard drives to function correctly, and this adds to the overall cost. RAID cannot protect the data and offer a performance boost for all applications. RAID should be maintained by commercial consultants. RAID configuration is difficult. Module 15 Page 1859 Certified Cybersecurity Technician Copyright © by EG-Council All Rights Reserved. Reproduction is Strictly Prohibited. Certified Cybersecurity Technician Exam 212-82 Data Security Configuration ’ Network Network Connection Connection to Host to Host e Data w = L A b RAID RAID Journal, Journal, > SORAM SDRAM A Y.4 to:::lu Cm“:.:m Transaction, (< )> SAN/NAS/Host SAN/NAS/Host and Error Log and Log © 7 oimm DIMM ‘ Tntetiace Firmware File 3 ] A pee " Interface ‘ SN File A A A <............................................... Corerrrnnnnnns P é Y........................... | (YTTTROTPIPPIIPPIPIITS Veriigmusniiiinn Xeceanen C............. > SPPPRRARPRRRPPRPRPT S S S —l 11 \MHDMMI 24 Controller Controller éromur éw A4 v Processor J RAID Contrel RAID Control Processor | G- 1 SAS/SATA Interfaces S S NAND 7. NanD J Fuas SAS/SATA Interfaces = >V.A J FLASH =TI =sua—ry e—sunm—n) =TT - Battery Backup or Ultracapacitor | 8 Unit v2 Y v Y SATIISAS Elplndir SATA/SAS Expander 2 A A A Primary RAID Memory Cache 5 & = = Copyright pyrig ©© byby ¥ All Rights Rights Rese Reserved, prved, Reproduction Reproduction F IsIs Strictly Prohibited, Strictly Prohibite RAID Storage Architecture (Cont’d) RAID Controller Manages an array of physical disk drives and presents them to the computer as logical units Intexface IDE, SATA, or SCSI Interface Internal drives are connected using these interfaces; Connection to the server is also through one of these interfaces..e Multiport Memory Controller Provides access to a memory bank, and helps achieve a high efficiency with random address accesses ", SDRAM Dynamic random access memory (DRAM) that is synchronized. with the CPU clock speed Copyright © by All Rights1ts Reserved. Reproduction IsIs Strictly Prohibited Module 15 Page 1860 Certified Cybersecurity Technician Copyright © by EG-Gouncil EC-Council All Rights Reserved. Reproduction is Strictly Prohibited.