VERY IMPORTANT NOTE! - RAID

Size: px
Start display at page:

Download "VERY IMPORTANT NOTE! - RAID"

Transcription

1 Disk drives are an integral part of any computing system. Disk drives are usually where the operating system and all of an enterprise or individual s data are stored. They are also one of the weakest links in a computing system. There are disk platters rotating at 7.2k to 15k RPMs, read and write heads moving over the rotating platters at a high rate of speed, and the data is magnetically written to the platter. A Disk drive is subject to failure due to shock, wear and tear on bearings, accidental erasure from magnetic fields, and damage from electrostatic discharge or power surges. For an individual, company, or enterprise that cannot tolerate system downtime, it makes sense to plan and implement contingency plans for the near-certainty that a hard drive is going to fail. When properly implemented, RAID can help maintain data availability when one or more disk drives fail. RAID is an acronym for Redundant Array of Independent Disks. In the early days of RAID, it was sometimes called Redundant Array of Inexpensive Disks. Both terms describe the same thing: A method of utilizing a number of disks for data storage. Why use multiple disks? There are three primary reasons: 1) Increased storage capacity - The maximum size of hard drives is increasing; every 8 months to a year the technology advances and it becomes possible to build a hard drive that will hold more data, and its barely keeping up with demand due to virtualized computing. 2) Increased performance when striping - Multiple drives can be used in a scheme where the data is striped across multiple drives. Consider this example: Suppose you had data that takes T seconds to write to a single disk. If you striped across two disks it would only take T/2 since you don t have to wait. This is multiplexing across a stripe. To stripe across n drives, it would take T/n. The more drives you have in a stripe, the faster you can write since mechanical drive speeds are orders of magnitude slower than processor or RAID HW speeds. 3) Data Availability (Fault tolerance) - If you only have one drive, and it fails, you are down until you can install a new drive and copy your backup data to this drive. Utilizing any RAID scheme (other and RAID 0), it is possible to create a scheme in which a drive failure(s) can be tolerated. That means, the system will stay up and running and data will not be lost. Of course, there can be combinations of the above reasons for using multiple drives, and there are different types of RAID or RAID Levels to address these requirements. VERY IMPORTANT NOTE! - RAID is NOT a substitute for backup! RAID offers a level of defense against a certain amount of failure. BUT - If an unlikely, unforeseen catastrophic event occurs, data can be lost in spite of even the most thorough implementation of RAID. Always formulate a solid backup and disaster recovery plan that will enable recovery from a worstcase scenario, such as complete destruction from fire, flood, tornado, etc. NAS (Network Attached Storage) devices with frequent snapshots are a good method of disaster recovery.

2 Let s look at different RAID levels and examine the advantages and weaknesses. RAID 0 - Striping Disk 0 Disk 1 A1 A2 B1 B2 RAID 0 requires a minimum of 2 disks, and it stripes the data across disks. The system sees the RAID array as one volume. When using two disks, the RAID controller simultaneously places one part of the file on disk one and the next part of the file on disk 2. The diagram above shows two write operations, A and B. Part of write operation A is written to disk 0 and part of write operation A is written to disk 1, and write operation B is striped in the same fashion. Since the write operation to each disk involves half of the file, writing the file takes about half the time it would take if there were a single disk. RAID 0 has a number of positive aspects: it speeds up read and write operation, all of the disk space is usable, and it is the least expensive form of RAID to implement. It does have a major shortcoming in that it leaves out one part of the RAID acronym Redundancy. With RAID 0, parts of files are stored on multiple drives. If one of the drives fails, all data is lost. There is no fault tolerance. In fact since there are multiple disks, there are more opportunities for failure. RAID 1 Mirroring Disk 0 Disk 1 A1 A1 A2 A2 B1 B1 B2 B2 In simplest form, RAID 1 consists of two drives storing duplicate data, but appear as a single volume to the system. It provides fault tolerance if one drive fails, the remaining drive contains all of the data that was on the failed drive. RAID 1 is the only RAID level that offers redundancy with only two disks. RAID 1 degrades write performance because the data has to be written twice. RAID 1 also cuts the storage capacity in half. If two 1TB drives are used in a RAID 1 array, their total capacity is 2TB, but only 1TB is available - the remaining 1TB is duplicate data.

3 RAID 10 Striping and Mirroring RAID 1 RAID 0 RAID 0 Disk 0 Disk 1 Disk 2 Disk 3 A1 A2 A1 A2 B1 B2 B1 B2 RAID 10 is a combination of RAID 0 and RAID 1. It is also a nested RAID because it nests RAID 0 arrays under a RAID 1 array. In the diagram above, notice disk 0 and disk 1 data is being mirrored to disk 2 and disk 3. RAID 10 takes a RAID 0 stripe, and mirrors data across the different spans. This offers a level of redundancy. If any one drive fails, functionality will continue. If both drives on one side of one of the Mirrors fail, functionality will continue. Note that disk 0 and disk 2 are identical, and disk 1 and disk 3 are identical. If disks 0 and 2 both fail, the system will fail because the data they contain is not available anywhere else. The same is true with disks 1 and 3. Like any of the other RAID schemes that use mirroring, only half of the total disk space is available for storage; the other half is devoted to the mirror image. RAID 5 Striping with Parity Disk 0 Disk 1 Disk 2 Disk 3 P 1 A1 A2 A3 B1 P 2 B2 B3 C1 C2 P 3 C3 D1 D2 D3 P 4 RAID 5 utilizes data striping like RAID 0, but introduces parity to the scheme. Parity is an extra bit of information that is computed and written along with the data. It can be checked later to assure that all data arrived as it was transmitted. When coupled with RAID, it can be used to rebuild a failed drive on the fly. RAID 5 requires a minimum of 3 drives. When data is written to a RAID 5 array, the data is striped across all members. In addition, a parity block is written to a different drive with each striping cycle. This is sometimes referred to as rotating parity, and gives RAID 5 the ability to tolerate the failure of any one drive in the array. The failure of a second drive will result in the loss of all data. When a single drive failure occurs, the system degrades to a RAID 0 configuration, and has no fault tolerance. When the failed drive is replaced, the system does not instantly achieve the fault-tolerance it had before the failure. The new drive must be rebuilt and re-integrated before fault tolerance is achieved. This means that in the period from the replacement of the drive until it is fully re-integrated, if another drive fails, all data will be lost. The larger the drive array, the more time this can take. Depending on the size of the drive array, rebuilding could take hours or even days, weeks or months. That is a lot of time to leave data vulnerable That is why backup and disaster recovery strategies are so important.

4 When a RAID 5 array is healthy with no failed disks, read operations are relatively fast, for the same reasons RAID 0 is fast data is being simultaneously read from multiple disks. For write operations, the writing of parity bits adds some overhead, so write performance is not as good as RAID levels that do not use parity. In many cases, the fault tolerance and disk utilization that is achieved with RAID 5 can make the performance tradeoff worthwhile. It is important to note that parity takes up some of the usable disk space, but significantly less space than is used with RAID levels that mirror drives. RAID 5 requires one disk worth of space for parity, so adding more disks to the array can reduce this overhead. RAID 50 Nesting RAID 5 Arrays in a RAID 0 Striping Array RAID 0 RAID 5 RAID 5 Disk 0 Disk 1 Disk 2 Disk 3 Disk 4 Disk 5 Disk 6 Disk 7 P 01 A01 A02 A03 P 11 A11 A12 A13 B01 P 02 B02 B03 B11 P 12 B12 B13 C01 C02 P 03 C03 C11 C12 P 13 C13 D01 D02 D03 P 04 D11 D12 D13 P 14 RAID 50 nests a number of RAID 5 arrays under a RAID 0 array. Remember that RAID 5 uses striping and parity, and RAID 0 uses striping, but no parity. RAID 0 has no fault tolerance, while RAID 5 can tolerate the failure of one disk. As we have seen previously, if a RAID 0 array loses a member, all data is lost. This is still true with a RAID 50 array, but now each member of the RAID 0 array is not a single disk, but a RAID 50 Array, and each RAID 50 array can tolerate the failure of one disk. RAID 50 could withstand one drive failure in each RAID 5 array (up to 4 disks in the example above) and keep functioning. A second drive failure in one of the individual RAID 5 array would cause all data to be lost. When a disk fails in a RAID 50 array, performance is degraded, and remains so until the disk is replaced AND the new disk is rebuilt and integrated into the array. RAID 50 s degraded performance is worse than RAID 0 s degraded performance, but better than RAID 5 s degraded performance. It is important to note that a RAID 50 array is not immediately healed and is NOT fully functional at the moment the failed drive is replaced. Time is required to rebuild the failed drive onto the new drive. The larger the drives, the more time required. For extremely large drive arrays, this could be hours or even days, weeks or months a lot of time for ALL of your data to be vulnerable. It is good practice to break up the data array in multiple LUNs as opposed to one single large volume for this reason.

5 RAID 6 Striping with Dual Parity Disk 0 Disk 1 Disk 2 Disk 3 P 1 P 2 A B C D P 3 P 4 P 5 P 6 E F G H P 7 P 8 RAID 6 is also a striping and parity scheme, but the difference between RAID 5 and RAID 6 is that RAID 6 utilizes two parity calculations per write operation, whereas RAID 5 utilizes one parity calculation per write operation. RAID 6 requires a minimum of four drives, and will tolerate the failure of any two drives. Upon the failure of the third drive, all data is lost. This additional fault tolerance comes at a cost. During write operations, a RAID 6 controller must calculate and write two parity blocks for each write operation. This takes time, making RAID 6 write performance slower than other RAID schemes. RAID 60 Nesting RAID 6 Arrays in RAID 0 Striping Array RAID 0 RAID 6 RAID 6 Disk 0 Disk 1 Disk 2 Disk 3 Disk 4 Disk 5 Disk 6 Disk 7 P 01 P 02 A0 B0 P 11 P 12 A1 B1 C0 D0 P 03 P 04 C1 D1 P 13 P 14 P 05 P 06 E0 F0 P 15 P 16 E1 F1 G0 H0 P 07 P 08 G1 H1 P 17 P 18 RAID 60 takes multiple RAID 6 arrays and nests them in a RAID 0 array, in a similar fashion to the way RAID 50 stripes individual disks. It has higher fault tolerance and can survive two disk faults per RAID 6 array.

6 RAID levels compared in a 12 disk NAS system RAID LEVEL Method Fault Tolerance Disk utilization (efficiency) Read Performance Write Performance RAID 0 Striping across disks None 100% Highest Highest RAID 1 Mirroring disks 1 Disk 50% High Low RAID 10 Stripe mirrored arrays Up to 1 disk failure in each sub-array 50% High High RAID 5 Striping and Single Parity across disks 1 Disk 91.67% High Low RAID 50 Striping across RAID 5 arrays Up to 1 disk failure in each sub-array 91.67% High Medium RAID 6 Striping and Dual Parity across disks 2 disks 83.33% High Lowest RAID 60 Striping across RAID 6 arrays Up to 2 disks failure in each sub-array 83.33% High Medium

PIONEER RESEARCH & DEVELOPMENT GROUP

PIONEER RESEARCH & DEVELOPMENT GROUP SURVEY ON RAID Aishwarya Airen 1, Aarsh Pandit 2, Anshul Sogani 3 1,2,3 A.I.T.R, Indore. Abstract RAID stands for Redundant Array of Independent Disk that is a concept which provides an efficient way for

More information

Click on the diagram to see RAID 0 in action

Click on the diagram to see RAID 0 in action Click on the diagram to see RAID 0 in action RAID Level 0 requires a minimum of 2 drives to implement RAID 0 implements a striped disk array, the data is broken down into blocks and each block is written

More information

RAID Level Descriptions. RAID 0 (Striping)

RAID Level Descriptions. RAID 0 (Striping) RAID Level Descriptions RAID 0 (Striping) Offers low cost and maximum performance, but offers no fault tolerance; a single disk failure results in TOTAL data loss. Businesses use RAID 0 mainly for tasks

More information

How to choose the right RAID for your Dedicated Server

How to choose the right RAID for your Dedicated Server Overview of RAID Let's first address, "What is RAID and what does RAID stand for?" RAID, an acronym for "Redundant Array of Independent Disks, is a storage technology that links or combines multiple hard

More information

RAID Made Easy By Jon L. Jacobi, PCWorld

RAID Made Easy By Jon L. Jacobi, PCWorld 9916 Brooklet Drive Houston, Texas 77099 Phone 832-327-0316 www.safinatechnolgies.com RAID Made Easy By Jon L. Jacobi, PCWorld What is RAID, why do you need it, and what are all those mode numbers that

More information

RAID 6 with HP Advanced Data Guarding technology:

RAID 6 with HP Advanced Data Guarding technology: RAID 6 with HP Advanced Data Guarding technology: a cost-effective, fault-tolerant solution technology brief Abstract... 2 Introduction... 2 Functions and limitations of RAID schemes... 3 Fault tolerance

More information

RAID HARDWARE. On board SATA RAID controller. RAID drive caddy (hot swappable) SATA RAID controller card. Anne Watson 1

RAID HARDWARE. On board SATA RAID controller. RAID drive caddy (hot swappable) SATA RAID controller card. Anne Watson 1 RAID HARDWARE On board SATA RAID controller SATA RAID controller card RAID drive caddy (hot swappable) Anne Watson 1 RAID The word redundant means an unnecessary repetition. The word array means a lineup.

More information

Disaster Recovery for Small Businesses

Disaster Recovery for Small Businesses Technical White Paper Disaster Recovery for Small Businesses A disaster recovery plan helps you understand what data is critical to your business operations and how to best protect it from unexpected failures.

More information

Storage node capacity in RAID0 is equal to the sum total capacity of all disks in the storage node.

Storage node capacity in RAID0 is equal to the sum total capacity of all disks in the storage node. RAID configurations defined 1/7 Storage Configuration: Disk RAID and Disk Management > RAID configurations defined Next RAID configurations defined The RAID configuration you choose depends upon how you

More information

SSDs and RAID: What s the right strategy. Paul Goodwin VP Product Development Avant Technology

SSDs and RAID: What s the right strategy. Paul Goodwin VP Product Development Avant Technology SSDs and RAID: What s the right strategy Paul Goodwin VP Product Development Avant Technology SSDs and RAID: What s the right strategy Flash Overview SSD Overview RAID overview Thoughts about Raid Strategies

More information

RAID Basics Training Guide

RAID Basics Training Guide RAID Basics Training Guide Discover a Higher Level of Performance RAID matters. Rely on Intel RAID. Table of Contents 1. What is RAID? 2. RAID Levels RAID 0 RAID 1 RAID 5 RAID 6 RAID 10 RAID 0+1 RAID 1E

More information

Using RAID6 for Advanced Data Protection

Using RAID6 for Advanced Data Protection Using RAI6 for Advanced ata Protection 2006 Infortrend Corporation. All rights reserved. Table of Contents The Challenge of Fault Tolerance... 3 A Compelling Technology: RAI6... 3 Parity... 4 Why Use RAI6...

More information

IncidentMonitor Server Specification Datasheet

IncidentMonitor Server Specification Datasheet IncidentMonitor Server Specification Datasheet Prepared by Monitor 24-7 Inc October 1, 2015 Contact details: sales@monitor24-7.com North America: +1 416 410.2716 / +1 866 364.2757 Europe: +31 088 008.4600

More information

technology brief RAID Levels March 1997 Introduction Characteristics of RAID Levels

technology brief RAID Levels March 1997 Introduction Characteristics of RAID Levels technology brief RAID Levels March 1997 Introduction RAID is an acronym for Redundant Array of Independent Disks (originally Redundant Array of Inexpensive Disks) coined in a 1987 University of California

More information

Data Integrity: Backups and RAID

Data Integrity: Backups and RAID Data Integrity: Backups and RAID Introduction Keeping your data safe and reliable TM Backups Types of backups Strategy Tools RAID (Redundant Array of Independent Disks) Types of RAID What type to Use Disk

More information

RAID Levels and Components Explained Page 1 of 23

RAID Levels and Components Explained Page 1 of 23 RAID Levels and Components Explained Page 1 of 23 What's RAID? The purpose of this document is to explain the many forms or RAID systems, and why they are useful, and their disadvantages. RAID - Redundant

More information

DELL RAID PRIMER DELL PERC RAID CONTROLLERS. Joe H. Trickey III. Dell Storage RAID Product Marketing. John Seward. Dell Storage RAID Engineering

DELL RAID PRIMER DELL PERC RAID CONTROLLERS. Joe H. Trickey III. Dell Storage RAID Product Marketing. John Seward. Dell Storage RAID Engineering DELL RAID PRIMER DELL PERC RAID CONTROLLERS Joe H. Trickey III Dell Storage RAID Product Marketing John Seward Dell Storage RAID Engineering http://www.dell.com/content/topics/topic.aspx/global/products/pvaul/top

More information

What is RAID and how does it work?

What is RAID and how does it work? What is RAID and how does it work? What is RAID? RAID is the acronym for either redundant array of inexpensive disks or redundant array of independent disks. When first conceived at UC Berkley the former

More information

The idea behind RAID is to have a number of disks co-operate in such a way that it looks like one big disk.

The idea behind RAID is to have a number of disks co-operate in such a way that it looks like one big disk. People often ask: Should I RAID my disks? The question is simple, unfortunately the answer is not. So here is a guide to help you decide when a RAID array is advantageous and how to go about it. This guide

More information

RAID Overview: Identifying What RAID Levels Best Meet Customer Needs. Diamond Series RAID Storage Array

RAID Overview: Identifying What RAID Levels Best Meet Customer Needs. Diamond Series RAID Storage Array ATTO Technology, Inc. Corporate Headquarters 155 Crosspoint Parkway Amherst, NY 14068 Phone: 716-691-1999 Fax: 716-691-9353 www.attotech.com sales@attotech.com RAID Overview: Identifying What RAID Levels

More information

Lecture 36: Chapter 6

Lecture 36: Chapter 6 Lecture 36: Chapter 6 Today s topic RAID 1 RAID Redundant Array of Inexpensive (Independent) Disks Use multiple smaller disks (c.f. one large disk) Parallelism improves performance Plus extra disk(s) for

More information

Definition of RAID Levels

Definition of RAID Levels RAID The basic idea of RAID (Redundant Array of Independent Disks) is to combine multiple inexpensive disk drives into an array of disk drives to obtain performance, capacity and reliability that exceeds

More information

ISTANBUL AYDIN UNIVERSITY

ISTANBUL AYDIN UNIVERSITY ISTANBUL AYDIN UNIVERSITY 2013-2014 Academic Year Fall Semester Department of Software Engineering SEN361 COMPUTER ORGANIZATION HOMEWORK REPORT STUDENT S NAME : GÖKHAN TAYMAZ STUDENT S NUMBER : B1105.090068

More information

An Introduction to RAID 6 ULTAMUS TM RAID

An Introduction to RAID 6 ULTAMUS TM RAID An Introduction to RAID 6 ULTAMUS TM RAID The highly attractive cost per GB of SATA storage capacity is causing RAID products based on the technology to grow in popularity. SATA RAID is now being used

More information

Deploying a File Server Lesson 2

Deploying a File Server Lesson 2 Deploying a File Server Lesson 2 Skills Matrix Technology Skill Objective Domain Objective # Adding a New Disk Configure storage 1.5 File Server The most basic and the most universal type of application

More information

Availability and Disaster Recovery: Basic Principles

Availability and Disaster Recovery: Basic Principles Availability and Disaster Recovery: Basic Principles by Chuck Petch, WVS Senior Technical Writer At first glance availability and recovery may seem like opposites. Availability involves designing computer

More information

Operating Systems. RAID Redundant Array of Independent Disks. Submitted by Ankur Niyogi 2003EE20367

Operating Systems. RAID Redundant Array of Independent Disks. Submitted by Ankur Niyogi 2003EE20367 Operating Systems RAID Redundant Array of Independent Disks Submitted by Ankur Niyogi 2003EE20367 YOUR DATA IS LOST@#!! Do we have backups of all our data???? - The stuff we cannot afford to lose?? How

More information

Introduction. What is RAID? The Array and RAID Controller Concept. Click here to print this article. Re-Printed From SLCentral

Introduction. What is RAID? The Array and RAID Controller Concept. Click here to print this article. Re-Printed From SLCentral Click here to print this article. Re-Printed From SLCentral RAID: An In-Depth Guide To RAID Technology Author: Tom Solinap Date Posted: January 24th, 2001 URL: http://www.slcentral.com/articles/01/1/raid

More information

Block1. Block2. Block3. Block3 Striping

Block1. Block2. Block3. Block3 Striping Introduction to RI Team members: 電 機 一 94901150 王 麒 鈞, 電 機 一 94901151 吳 炫 逸, 電 機 一 94901154 孫 維 隆. Motivation Gosh, my hard disk is broken again, and my computer can t boot normally. I even have no chance

More information

Guide to SATA Hard Disks Installation and RAID Configuration

Guide to SATA Hard Disks Installation and RAID Configuration Guide to SATA Hard Disks Installation and RAID Configuration 1. Guide to SATA Hard Disks Installation...2 1.1 Serial ATA (SATA) Hard Disks Installation...2 2. Guide to RAID Configurations...3 2.1 Introduction

More information

USER GUIDE. PageScope Enterprise Suite. Backup and Recovery

USER GUIDE. PageScope Enterprise Suite. Backup and Recovery PageScope Enterprise Suite Backup and Recovery USER GUIDE Date : 07/31/2008 Written by: Tony Gliatta, Vartkes Tashjian and Rob Posenato Location: CEC Lab, HQ Ramsey, NJ Table of Content Chapter 1 PageScope

More information

Overview of I/O Performance and RAID in an RDBMS Environment. By: Edward Whalen Performance Tuning Corporation

Overview of I/O Performance and RAID in an RDBMS Environment. By: Edward Whalen Performance Tuning Corporation Overview of I/O Performance and RAID in an RDBMS Environment By: Edward Whalen Performance Tuning Corporation Abstract This paper covers the fundamentals of I/O topics and an overview of RAID levels commonly

More information

Data Storage - II: Efficient Usage & Errors

Data Storage - II: Efficient Usage & Errors Data Storage - II: Efficient Usage & Errors Week 10, Spring 2005 Updated by M. Naci Akkøk, 27.02.2004, 03.03.2005 based upon slides by Pål Halvorsen, 12.3.2002. Contains slides from: Hector Garcia-Molina

More information

CS420: Operating Systems

CS420: Operating Systems NK YORK COLLEGE OF PENNSYLVANIA HG OK 2 RAID YORK COLLEGE OF PENNSYLVAN James Moscola Department of Physical Sciences York College of Pennsylvania Based on Operating System Concepts, 9th Edition by Silberschatz,

More information

OPTIMIZING VIRTUAL TAPE PERFORMANCE: IMPROVING EFFICIENCY WITH DISK STORAGE SYSTEMS

OPTIMIZING VIRTUAL TAPE PERFORMANCE: IMPROVING EFFICIENCY WITH DISK STORAGE SYSTEMS W H I T E P A P E R OPTIMIZING VIRTUAL TAPE PERFORMANCE: IMPROVING EFFICIENCY WITH DISK STORAGE SYSTEMS By: David J. Cuddihy Principal Engineer Embedded Software Group June, 2007 155 CrossPoint Parkway

More information

Security+ Guide to Network Security Fundamentals, Fourth Edition. Chapter 13 Business Continuity

Security+ Guide to Network Security Fundamentals, Fourth Edition. Chapter 13 Business Continuity Security+ Guide to Network Security Fundamentals, Fourth Edition Chapter 13 Business Continuity Objectives Define environmental controls Describe the components of redundancy planning List disaster recovery

More information

REMOTE OFFICE BACKUP

REMOTE OFFICE BACKUP REMOTE OFFICE BACKUP Remote offices present IT managers with a number of technical challenges. Often businesses use remote offices to expand into either new markets, or into new geographical areas. Many

More information

Distribution One Server Requirements

Distribution One Server Requirements Distribution One Server Requirements Introduction Welcome to the Hardware Configuration Guide. The goal of this guide is to provide a practical approach to sizing your Distribution One application and

More information

Moving Beyond RAID DXi and Dynamic Disk Pools

Moving Beyond RAID DXi and Dynamic Disk Pools TECHNOLOGY BRIEF Moving Beyond RAID DXi and Dynamic Disk Pools NOTICE This Technology Brief contains information protected by copyright. Information in this Technology Brief is subject to change without

More information

StorTrends RAID Considerations

StorTrends RAID Considerations StorTrends RAID Considerations MAN-RAID 04/29/2011 Copyright 1985-2011 American Megatrends, Inc. All rights reserved. American Megatrends, Inc. 5555 Oakbrook Parkway, Building 200 Norcross, GA 30093 Revision

More information

Guide to SATA Hard Disks Installation and RAID Configuration

Guide to SATA Hard Disks Installation and RAID Configuration Guide to SATA Hard Disks Installation and RAID Configuration 1. Guide to SATA Hard Disks Installation... 2 1.1 Serial ATA (SATA) Hard Disks Installation... 2 2. Guide to RAID Configurations... 3 2.1 Introduction

More information

RAID Technology White Paper

RAID Technology White Paper RAID Technology White Paper As specialists in data storage, LaCie recognizes that almost all computer users will need a storage or backup solution and that people use and store data in different ways.

More information

Technical White paper RAID Protection and Drive Failure Fast Recovery

Technical White paper RAID Protection and Drive Failure Fast Recovery Technical White paper RAID Protection and Drive Failure Fast Recovery RAID protection is a key part of all ETERNUS Storage Array products. Choices of the level chosen to meet customer application requirements

More information

200 Chapter 7. (This observation is reinforced and elaborated in Exercises 7.5 and 7.6, and the reader is urged to work through them.

200 Chapter 7. (This observation is reinforced and elaborated in Exercises 7.5 and 7.6, and the reader is urged to work through them. 200 Chapter 7 (This observation is reinforced and elaborated in Exercises 7.5 and 7.6, and the reader is urged to work through them.) 7.2 RAID Disks are potential bottlenecks for system performance and

More information

Storage Technologies for Video Surveillance

Storage Technologies for Video Surveillance The surveillance industry continues to transition from analog to digital. This transition is taking place on two fronts how the images are captured and how they are stored. The way surveillance images

More information

Non-Redundant (RAID Level 0)

Non-Redundant (RAID Level 0) There are many types of RAID and some of the important ones are introduced below: Non-Redundant (RAID Level 0) A non-redundant disk array, or RAID level 0, has the lowest cost of any RAID organization

More information

Blackboard Managed Hosting SM Disaster Recovery Planning Document

Blackboard Managed Hosting SM Disaster Recovery Planning Document BLACKBOARD MANAGED HOSTING Blackboard Managed Hosting SM Disaster Recovery Planning Document Prepared By: MH Services Modified Date: March 2009 Revision: 1.8 1. OBJECTIVES... 3 2. SCOPE... 3 3. ASSUMPTIONS...

More information

Best Practices RAID Implementations for Snap Servers and JBOD Expansion

Best Practices RAID Implementations for Snap Servers and JBOD Expansion STORAGE SOLUTIONS WHITE PAPER Best Practices RAID Implementations for Snap Servers and JBOD Expansion Contents Introduction...1 Planning for the End Result...1 Availability Considerations...1 Drive Reliability...2

More information

RAID Technology Overview

RAID Technology Overview RAID Technology Overview HP Smart Array RAID Controllers HP Part Number: J6369-90050 Published: September 2007 Edition: 1 Copyright 2007 Hewlett-Packard Development Company L.P. Legal Notices Copyright

More information

GENERAL INFORMATION COPYRIGHT... 3 NOTICES... 3 XD5 PRECAUTIONS... 3 INTRODUCTION... 4 FEATURES... 4 SYSTEM REQUIREMENT... 4

GENERAL INFORMATION COPYRIGHT... 3 NOTICES... 3 XD5 PRECAUTIONS... 3 INTRODUCTION... 4 FEATURES... 4 SYSTEM REQUIREMENT... 4 1 Table of Contents GENERAL INFORMATION COPYRIGHT... 3 NOTICES... 3 XD5 PRECAUTIONS... 3 INTRODUCTION... 4 FEATURES... 4 SYSTEM REQUIREMENT... 4 XD5 FAMILULARIZATION... 5 PACKAGE CONTENTS... 5 HARDWARE

More information

RAID: Redundant Arrays of Independent Disks

RAID: Redundant Arrays of Independent Disks RAID: Redundant Arrays of Independent Disks Dependable Systems Dr.-Ing. Jan Richling Kommunikations- und Betriebssysteme TU Berlin Winter 2012/2013 RAID: Introduction Redundant array of inexpensive disks

More information

New Advanced RAID Level for Today's Larger Storage Capacities: Advanced Data Guarding

New Advanced RAID Level for Today's Larger Storage Capacities: Advanced Data Guarding White Paper October 2000 Prepared by Storage Products Group Compaq Computer Corporation Contents Introduction...2 What customers can expect from Compaq RAID ADG solution...3 RAID ADG Features and Benefits...3

More information

Dependable Systems. 9. Redundant arrays of. Prof. Dr. Miroslaw Malek. Wintersemester 2004/05 www.informatik.hu-berlin.de/rok/zs

Dependable Systems. 9. Redundant arrays of. Prof. Dr. Miroslaw Malek. Wintersemester 2004/05 www.informatik.hu-berlin.de/rok/zs Dependable Systems 9. Redundant arrays of inexpensive disks (RAID) Prof. Dr. Miroslaw Malek Wintersemester 2004/05 www.informatik.hu-berlin.de/rok/zs Redundant Arrays of Inexpensive Disks (RAID) RAID is

More information

Practical issues in DIY RAID Recovery

Practical issues in DIY RAID Recovery www.freeraidrecovery.com Practical issues in DIY RAID Recovery Based on years of technical support experience 2012 www.freeraidrecovery.com This guide is provided to supplement our ReclaiMe Free RAID Recovery

More information

Nutanix Tech Note. Failure Analysis. 2013 All Rights Reserved, Nutanix Corporation

Nutanix Tech Note. Failure Analysis. 2013 All Rights Reserved, Nutanix Corporation Nutanix Tech Note Failure Analysis A Failure Analysis of Storage System Architectures Nutanix Scale-out v. Legacy Designs Types of data to be protected Any examination of storage system failure scenarios

More information

RAID5 versus RAID10. First let's get on the same page so we're all talking about apples.

RAID5 versus RAID10. First let's get on the same page so we're all talking about apples. RAID5 versus RAID10 First let's get on the same page so we're all talking about apples. What is RAID? RAID originally stood for Redundant Arrays of Inexpensive Disk and was an idea proposed in the early

More information

an analysis of RAID 5DP

an analysis of RAID 5DP an analysis of RAID 5DP a qualitative and quantitative comparison of RAID levels and data protection hp white paper for information about the va 7000 series and periodic updates to this white paper see

More information

Storage Options for Document Management

Storage Options for Document Management Storage Options for Document Management Document management and imaging systems store large volumes of data, which must be maintained for long periods of time. Choosing storage is not simply a matter of

More information

June 2009. Blade.org 2009 ALL RIGHTS RESERVED

June 2009. Blade.org 2009 ALL RIGHTS RESERVED Contributions for this vendor neutral technology paper have been provided by Blade.org members including NetApp, BLADE Network Technologies, and Double-Take Software. June 2009 Blade.org 2009 ALL RIGHTS

More information

CHAPTER 4 RAID. Section Goals. Upon completion of this section you should be able to:

CHAPTER 4 RAID. Section Goals. Upon completion of this section you should be able to: HPTER 4 RI s it was originally proposed, the acronym RI stood for Redundant rray of Inexpensive isks. However, it has since come to be known as Redundant rray of Independent isks. RI was originally described

More information

Read this before starting!

Read this before starting! Points missed: Student's Name: Total score: /100 points East Tennessee State University Department of Computer and Information Sciences CSCI 4717 Computer Architecture TEST 2 for Fall Semester, 2006 Section

More information

Disaster Preparedness for Information Technology

Disaster Preparedness for Information Technology Disaster Preparedness for Information Technology An overview of 4 main components to a disaster recovery plan. For owners or managers of professional offices. Written by Mark Haake, President of Reliance

More information

CS161: Operating Systems

CS161: Operating Systems CS161: Operating Systems Matt Welsh mdw@eecs.harvard.edu Lecture 18: RAID April 19, 2007 2007 Matt Welsh Harvard University 1 RAID Redundant Arrays of Inexpensive Disks Invented in 1986-1987 by David Patterson

More information

CSE-E5430 Scalable Cloud Computing P Lecture 5

CSE-E5430 Scalable Cloud Computing P Lecture 5 CSE-E5430 Scalable Cloud Computing P Lecture 5 Keijo Heljanko Department of Computer Science School of Science Aalto University keijo.heljanko@aalto.fi 12.10-2015 1/34 Fault Tolerance Strategies for Storage

More information

Assessing RAID ADG vs. RAID 5 vs. RAID 1+0

Assessing RAID ADG vs. RAID 5 vs. RAID 1+0 White Paper October 2001 Prepared by Industry Standard Storage Group Compaq Computer Corporation Contents Overview...3 Defining RAID levels...3 Evaluating RAID levels...3 Choosing a RAID level...4 Assessing

More information

Module 6. RAID and Expansion Devices

Module 6. RAID and Expansion Devices Module 6 RAID and Expansion Devices Objectives 1. PC Hardware A.1.5 Compare and contrast RAID types B.1.8 Compare expansion devices 2 RAID 3 RAID 1. Redundant Array of Independent (or Inexpensive) Disks

More information

Intransa EnterpriseServer and EnterpriseStorage Infrastructure for High Availability Needs V1.0

Intransa EnterpriseServer and EnterpriseStorage Infrastructure for High Availability Needs V1.0 Intransa EnterpriseServer and EnterpriseStorage Infrastructure for High Availability Needs V1.0 Introduction This document is designed to provide the reader with an overview of Intransa s High Availability

More information

RAID Implementation for StorSimple Storage Management Appliance

RAID Implementation for StorSimple Storage Management Appliance RAID Implementation for StorSimple Storage Management Appliance Alpa Kohli June, 2012 KB-00008 Document Revision 1 StorSimple knowledge base articles are intended to provide customers with the information

More information

HARD DRIVE CHARACTERISTICS REFRESHER

HARD DRIVE CHARACTERISTICS REFRESHER The read/write head of a hard drive only detects changes in the magnetic polarity of the material passing beneath it, not the direction of the polarity. Writes are performed by sending current either one

More information

NVIDIA RAID Installation Guide

NVIDIA RAID Installation Guide NVIDIA RAID Installation Guide 1. NVIDIA BIOS RAID Installation Guide.. 2 1.1 Introduction to RAID. 2 1.2 RAID Configurations Precautions.. 3 1.3 Create Disk Array. 4 2. NVIDIA Windows RAID Installation

More information

File System & Device Drive. Overview of Mass Storage Structure. Moving head Disk Mechanism. HDD Pictures 11/13/2014. CS341: Operating System

File System & Device Drive. Overview of Mass Storage Structure. Moving head Disk Mechanism. HDD Pictures 11/13/2014. CS341: Operating System CS341: Operating System Lect 36: 1 st Nov 2014 Dr. A. Sahu Dept of Comp. Sc. & Engg. Indian Institute of Technology Guwahati File System & Device Drive Mass Storage Disk Structure Disk Arm Scheduling RAID

More information

Getting Started With RAID

Getting Started With RAID Dell Systems Getting Started With RAID www.dell.com support.dell.com Notes, Notices, and Cautions NOTE: A NOTE indicates important information that helps you make better use of your computer. NOTICE: A

More information

CS 6290 I/O and Storage. Milos Prvulovic

CS 6290 I/O and Storage. Milos Prvulovic CS 6290 I/O and Storage Milos Prvulovic Storage Systems I/O performance (bandwidth, latency) Bandwidth improving, but not as fast as CPU Latency improving very slowly Consequently, by Amdahl s Law: fraction

More information

UK HQ RAID Chunk Size T F www.xyratex.com ISO 14001

UK HQ RAID Chunk Size T F www.xyratex.com ISO 14001 RAID Chunk Size Notices The information in this document is subject to change without notice. While every effort has been made to ensure that all information in this document is accurate, Xyratex accepts

More information

RAID. Storage-centric computing, cloud computing. Benefits:

RAID. Storage-centric computing, cloud computing. Benefits: RAID Storage-centric computing, cloud computing. Benefits: Improved reliability (via error correcting code, redundancy). Improved performance (via redundancy). Independent disks. RAID Level 0 Provides

More information

Chapter 6 External Memory. Dr. Mohamed H. Al-Meer

Chapter 6 External Memory. Dr. Mohamed H. Al-Meer Chapter 6 External Memory Dr. Mohamed H. Al-Meer 6.1 Magnetic Disks Types of External Memory Magnetic Disks RAID Removable Optical CD ROM CD Recordable CD-R CD Re writable CD-RW DVD Magnetic Tape 2 Introduction

More information

RAID Storage System of Standalone NVR

RAID Storage System of Standalone NVR ACTi Knowledge Base Category: Installation & Configuration Note Sub-category: Hardware; Recording & Storage Model: XNR-4200, GNR-2000 Firmware: Software: Author: Ando.Meritee Published: 2011/05/04 Reviewed:

More information

Home storage and backup options. Chris Moates Head of Lettuce

Home storage and backup options. Chris Moates Head of Lettuce Home storage and backup options Chris Moates Head of Lettuce Who I Am Lead Systems Architect/Administrator for Gaggle Previously employed as Staff Engineer by EarthLink/MindSpring Linux hobbyist since

More information

Fault Tolerance & Reliability CDA 5140. Chapter 3 RAID & Sample Commercial FT Systems

Fault Tolerance & Reliability CDA 5140. Chapter 3 RAID & Sample Commercial FT Systems Fault Tolerance & Reliability CDA 5140 Chapter 3 RAID & Sample Commercial FT Systems - basic concept in these, as with codes, is redundancy to allow system to continue operation even if some components

More information

NAS 251 Introduction to RAID

NAS 251 Introduction to RAID NAS 251 Introduction to RAID Set up a storage volume with RAID A S U S T O R C O L L E G E COURSE OBJECTIVES Upon completion of this course you should be able to: 1. Have a basic understanding of RAID

More information

XtremIO DATA PROTECTION (XDP)

XtremIO DATA PROTECTION (XDP) White Paper XtremIO DATA PROTECTION (XDP) Flash-Specific Data Protection, Provided by XtremIO (Ver..0) Abstract This white paper introduces the and discusses its benefits and advantages over RAID, with

More information

Business Continuity Requires the Best Cloud Storage Options

Business Continuity Requires the Best Cloud Storage Options Requires the Best Cloud Storage Options www.gr e xo.co m Requires the Best Cloud Storage Options Only about 38% of small to medium sized businesses have an IT business continuity plan in place. If you

More information

Linux Software Raid. Aug 2010. Mark A. Davis

Linux Software Raid. Aug 2010. Mark A. Davis Linux Software Raid Aug 2010 Mark A. Davis a What is RAID? Redundant Array of Inexpensive/Independent Drives It is a method of combining more than one hard drive into a logic unit for the purpose of: Increasing

More information

Intel RAID Software User s Guide:

Intel RAID Software User s Guide: Intel RAID Software User s Guide: Intel Embedded Server RAID Technology II Intel Integrated Server RAID Intel RAID Controllers using the Intel RAID Software Stack 3 Revision 8.0 August, 2008 Intel Order

More information

Data Backup Options for SME s

Data Backup Options for SME s Data Backup Options for SME s As an IT Solutions company, Alchemy are often asked what is the best backup solution? The answer has changed over the years and depends a lot on your situation. We recognize

More information

Which RAID Level is Right for Me?

Which RAID Level is Right for Me? STOR SOUTOS WT R Which R evel is Right for e? ontents ntroduction...1 R evel escriptions...1 R 0 ()...1 R 1 (irroring)...2 R 1 (Striped irror)...2 R 5 ( with parity)...2 R 5 (ot Space)...3 R 6 ( with dual

More information

Hard Disk Drives and RAID

Hard Disk Drives and RAID Hard Disk Drives and RAID Janaka Harambearachchi (Engineer/Systems Development) INTERFACES FOR HDD A computer interfaces is what allows a computer to send and retrieve information for storage devices such

More information

Summer Student Project Report

Summer Student Project Report Summer Student Project Report Dimitris Kalimeris National and Kapodistrian University of Athens June September 2014 Abstract This report will outline two projects that were done as part of a three months

More information

Input / Ouput devices. I/O Chapter 8. Goals & Constraints. Measures of Performance. Anatomy of a Disk Drive. Introduction - 8.1

Input / Ouput devices. I/O Chapter 8. Goals & Constraints. Measures of Performance. Anatomy of a Disk Drive. Introduction - 8.1 Introduction - 8.1 I/O Chapter 8 Disk Storage and Dependability 8.2 Buses and other connectors 8.4 I/O performance measures 8.6 Input / Ouput devices keyboard, mouse, printer, game controllers, hard drive,

More information

Traditionally, a typical SAN topology uses fibre channel switch wiring while a typical NAS topology uses TCP/IP protocol over common networking

Traditionally, a typical SAN topology uses fibre channel switch wiring while a typical NAS topology uses TCP/IP protocol over common networking Network Storage for Business Continuity and Disaster Recovery and Home Media White Paper Abstract Network storage is a complex IT discipline that includes a multitude of concepts and technologies, like

More information

Cisco Small Business NAS Storage

Cisco Small Business NAS Storage Cisco Small Business NAS Storage Stanislav.Hrda@alefnula.sk Session number:208 070 400 Bezplatné číslo (volanie cez Skype): +1 866 432 9903 Lokálny tel. pre Česko: +420 221 435 100 Lokálny tel. pre Slovensko:

More information

Disk Array Data Organizations and RAID

Disk Array Data Organizations and RAID Guest Lecture for 15-440 Disk Array Data Organizations and RAID October 2010, Greg Ganger 1 Plan for today Why have multiple disks? Storage capacity, performance capacity, reliability Load distribution

More information

TECHNOLOGY BRIEF. Compaq RAID on a Chip Technology EXECUTIVE SUMMARY CONTENTS

TECHNOLOGY BRIEF. Compaq RAID on a Chip Technology EXECUTIVE SUMMARY CONTENTS TECHNOLOGY BRIEF August 1999 Compaq Computer Corporation Prepared by ISSD Technology Communications CONTENTS Executive Summary 1 Introduction 3 Subsystem Technology 3 Processor 3 SCSI Chip4 PCI Bridge

More information

What is RAID--BASICS? Mylex RAID Primer. A simple guide to understanding RAID

What is RAID--BASICS? Mylex RAID Primer. A simple guide to understanding RAID What is RAID--BASICS? Mylex RAID Primer A simple guide to understanding RAID Let's look at a hard disk... Several platters stacked on top of each other with a little space in between. One to n platters

More information

Windows Server Performance Monitoring

Windows Server Performance Monitoring Spot server problems before they are noticed The system s really slow today! How often have you heard that? Finding the solution isn t so easy. The obvious questions to ask are why is it running slowly

More information

Maintenance Best Practices for Adaptec RAID Solutions

Maintenance Best Practices for Adaptec RAID Solutions Maintenance Best Practices for Adaptec RAID Solutions Note: This document is intended to provide insight into the best practices for routine maintenance of Adaptec RAID systems. These maintenance best

More information

Outline. Database Management and Tuning. Overview. Hardware Tuning. Johann Gamper. Unit 12

Outline. Database Management and Tuning. Overview. Hardware Tuning. Johann Gamper. Unit 12 Outline Database Management and Tuning Hardware Tuning Johann Gamper 1 Free University of Bozen-Bolzano Faculty of Computer Science IDSE Unit 12 2 3 Conclusion Acknowledgements: The slides are provided

More information

Performance Analysis of RAIDs in Storage Area Network

Performance Analysis of RAIDs in Storage Area Network Performance Analysis of RAIDs in Storage Area Network Sneha M. Assistant Professor, Department of Computer Science and Engineering, R V College of Engineering Bengaluru-560059 ABSTRACT Direct Attached

More information