Artificial intelligence , livre ebook

Computer Storage Fundamentals
By Susanta Dutta
First Edition 2018
Copyright © BPB Publication, INDIA
ISBN: 978-93-88176-55-2
All Rights Reserved. No part of this publication can be stored in a retrieval system or reproduced in any form or by any means without the prior written permission of the publishers.
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Published by Manish Jain for BPB Publications, 20, Ansari Road, Darya Ganj, New Delhi-110002 and Printed by Repro India Pvt Ltd, Mumbai
Preface
In today's competitive markets, students and IT professionals are more aggressive to create a differentiating factor over and above regular courses , and they are more curious to learn about industry-specific technologies that can help in technical interviews and as well as performing job more efficiently.
On the other hand, the enormous growth of digital information has significantly increased demand for storage job market in recent years. Today several universities, engineering colleges and educational institutes are offering undergraduate/ postgraduate courses on storage technologies.
There are plenty of storage vendors, who make storage products and implement solutions. Most vendors explain and advertise feature set for their products using their terminologies through internet blogs, videos etc. At times, it's hard to understand the context and underlying concept and larger objective of a feature and difficult to locate a document or write-up for conceptual understanding.
I wrote this book with the learnings captured from decades of working experience with storage technologies to fill the gap mentioned above and connect it with the need. This book explains the familiar concept of storage technologies without referring to or highlighting any vendor's product. It focuses on the fundamental and underlying concepts of storage technologies. Every Storage vendor builds their products using these technologies.
Therefore, the following readers would undoubtedly be benefited by the content of this book:
Engineering Students
Course/Syllabus that covers Storage Technologies
Step up skills for effective campus placement
IT Professionals
The ramp-up of the newly hired workforce
Upgrade talent of existing employees to perform the job efficiently and effectively.
Storage Administrators:
Administrators who, manage and monitor their deployed storage systems and solutions.
Acknowledgement
The work presented in this book would not have been possible without close association with my colleagues. Mentors, seniors and juniors, everyone contributed to this work directly or indirectly
I express my deepest and sincere gratitude to my senior Mr. Srikanth BK, who introduced me to Storage many years back and guided me to understand basic storage concepts.
I am also thankful to my organization, Hewlett-Packard Enterprise (HPE), for the opportunities and exposure to work with different of types of storage products and solutions.
Finally, I would like to thank my family for their love, support and blessings.
Table of Contents
Chapter 1: Storage System and Solutions
Chapter 2: Storage Infrastructure
Chapter 3: Storage Disk Array
Chapter 4: Storage Communication Protocols
Chapter 5: Storage Networking
Chapter 6: Storage Performance
Chapter 7: Fault Tolerance and Data Protection
Chapter 8: Space Efficiency
Chapter 9: Storage Management
Introduction
In today's modern world almost all information is in the form of digital data, such as e-mails, documents, spreadsheets, presentations, databases, graphics, audio, and image files. The explosive growth in the volume of digital data in last few years caused demand for more and more computer storage systems. To access and process data, it has become more important to store data faster and efficiently. Therefore computer storage skill has become the most important for all IT (Information Technology) professionals.
Almost all companies, small to large enterprises, deploy computers to meet their business objectives. These computers are primarily of three categories - Servers, Networking, and Storages. All these three components are interconnected to run business applications. Applications, run on Servers, read and write data stored on to the storage systems. Figure 1 : Servers, Network and Storage system
Hard disk drives were introduced in 1956 as data storage for an IBM system. Since then, storage evolved much higher to meet requirements of today's world. With advancement of computer, mobile and popularity of internet, social media, digital data is growing exponentially. Current total global data is almost double than what was there two years back. Not only is amount of data that is increasing, but also criticality of it is increasing significantly. This means impact due to the loss of digital data few years later, would be much more severe than today. At the same time demand for rate of accessing data is also increasing significantly.
To optimize and improve efficient resource sharing, a storage system is typically shared by multiple servers to store their data, therefore it's important to have a modern storage system with higher space efficiency, performance and fault tolerance. Figure 2 : Three aspects of a storage system
A storage system is considered to be best in the market, if it is capable of supporting higher degree of all three aspects.
Interesting part, most features of a storage system that improves one of these aspects, impacts of reduction of other aspects. For example, RAID0 improves Storage Performance, but reduces Fault tolerance, Deduplication improves storage efficiency, but impacts performance. It's a big challenge for storage vendors to develop a storage that provides all the three aspects of storage systems.
Most storage vendors develop and sale multiple storage applications to manage other aspect of Storage systems, such as performance, local and remote replication, backup and data recovery solutions.
About this Book
This book explains the basic concept of computer storage and its fundamental features and functionalities. It also includes topics on how the application servers access storage systems through the network.
Different storage vendors use different name for physical and logical components of a storage system, but this book primarily focuses on concept of storage systems using simple and commonly understood terminologies. Almost all modern storage systems have virtualization implemented to enhance performance and fault tolerance. This book explains these implementation aspects in simple terms.
This book also highlights the storage system usage in various solutions to meet enterprise company's business objectives.
This book consists of nine chapters. First chapter describes the different type of storage systems and their solutions. Next four chapters focus on the components of a storage solution, storage disk array, host servers, storage networking components and their communications. Later chapters explain storage performance, fault tolerance and space efficiency and their related features. The last chapter highlights storage management software suite that enables administrator to manage all storage hardware and software components and their features and functionalities that are discussed in earlier chapters.
Concepts are explained with examples, less words and more diagrams. Simple language is used throughout the book with to-the-point information.
At the end of each chapter, this book provides industry specific case studies for the reader to correlate learnings with actual and real facts.
This book also includes different type of learning checks for each chapter that helps to refresh learnings and enhance the learning experience. Learning checks are classified into three - objective type questions with multiple choice answers, descriptive questions and quiz questions focusing on problem solving, logical thinking, and storage solution based. Quiz questions can have short answer, yes/no or true/ false. These learning checks can also be considered as a topic for group discussions, in which, group of students, colleagues, or professionals can discuss and provide reasons to justify their answers.
Chapter 1
Storage Systems and Solutions

Learning objectives
This chapter discusses different type of storage systems, the technologies to store data and solutions that are deployed in small, medium, and large organizations. You will also learn about the pros and cons of all the storage systems with respect to their usages in the solutions.
Upon successful completion of this chapter, you will be able to learn about the following areas:
Type of storage systems: Block, File, and Object storage systems
Type of storage solutions:
DAS, NAS, SAN and Cloud storage
Entry level, mid-range and enterprise storage solutions
Storage solution components
Hyper-conve