RHCE: Red Hat Certified Engineer Study Guide Copyright ©2000 SYBEX , Inc., Alameda, CA www.sybex.com San Francisco • Paris • Düsseldorf • Soest • London RHCE: Red Hat Certified Engineer Study Guide Bill McCarty Copyright ©2000 SYBEX , Inc., Alameda, CA www.sybex.com Associate Publisher: Jordan Gold Contracts and Licensing Manager: Kristine O’Callaghan Acquisitions and Developmental Editor: Ellen L. Dendy Editors: Julie Sakaue, Suzanne Goraj, Sarah Lemaire Production Editor: Dennis Fitzgerald Technical Editor: Randolph Russell Book Designer: Bill Gibson Graphic Illustrator: Tony Jonick Electronic Publishing Specialists: Susie Hendrickson, Judy Fung, Jill Niles Proofreaders: Carol A. Burbo, Nanette Duffy, Mae Lum, Nathan Whiteside Indexer: Ted Laux CD Coordinator: Kara Eve Schwartz CD Technician: Keith McNeil Cover Designer: Archer Design Cover Photograph: Tony Stone Copyright © 2000 SYBEX Inc., 1151 Marina Village Parkway, Alameda, CA 94501. World rights reserved. 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Individual programs differ on details of trial periods, registration, and payment. Please observe the requirements stated in appropriate files. Copy Protection The Software in whole or in part may or may not be copy- protected or encrypted. However, in all cases, reselling or redistributing these files without authorization is expressly forbidden except as specifically provided for by the Owner(s) therein. Copyright ©2000 SYBEX , Inc., Alameda, CA www.sybex.com Acknowledgments T his is my tenth book, and I still find writing acknowledgments to be the hardest part of writing a book. This is doubly frustrating because they’re so seldom read, or so it seems to me. I’m a teacher during the day, you see, and I find that my students are only dimly and rarely aware of the acknowledg- ments in books they’ve bought at my insistence. Perhaps the acknowledgments in works of fiction enjoy a gladder fate, but the pessimist in me doubts that this is so. I don’t understand all this, because I’m the sort who watches the credits of a film until I see the copyright symbol go by. Okay, to be honest, I often skip out when I see the production accountants’ names go by, but that’s quite close to the end, isn’t it? Notwithstanding this conspiracy of obscurity that surrounds acknowl- edgments, I must insist that they’re important. Yes, I concede that it’s unlikely that more than a handful of people have ever purchased books on account of the acknowledgments. And, that seems to indicate that the acknowledgments are less important than what lies nearer the center of the book. But, not so. After all, books are created by people and for people : It’s people who are important, not books. And here, in the acknowledgments, I have an opportunity to pay a debt to the many people who worked on this book. In film, many people are sometimes given a prominent place in the credits—often above the title of the film itself—including producers, directors, actors, and actresses. But, in publish- ing, the cover of a book generally contains only the name of the publishing com- pany and the author. (Gosh, come to think of it, I haven’t seen the cover of this book: I’m merely presuming that my name will be on the cover.) This is all wrong, and I’d like to give you the chance to help change it: I want you to copy this page—don’t tear it out or anything crude like that— and tape it over the cover of your copy of this book. The result may not be very visually aesthetic, but my spirit soars when I consider this little act of rebellion against anonymity on behalf of the cast and crew of this book. Now, I’d best get to the point or the names of all these folk will be on the back of this page, which would ruin the whole concept, wouldn’t it? Let’s start with Margot Maley-Hutchison, Literary Agent (think of her as the producer), and Ellen Dendy, Acquisitions and Developmental Editor (think of her as the director). Then, there’s Randy Russell and Utilman, Technical Editors (think of them as the screenwriters who adapted my unfilmable novel, because that approximates the enormous scope of their Copyright ©2000 SYBEX , Inc., Alameda, CA www.sybex.com Acknowledgments vii contribution) and Ellen Bliss, Technical Editorial Coordinator (think of her as the screenwriting manager who had the wisdom to choose Randy and Utilman to write the screenplay). Stars include Dennis Fitzgerald, Production Editor (think of him as this year’s best actor); Julie Sakaue, Editor (think of her as this year’s best actress); and Sarah Lemaire and Suzanne Goraj, Editors (think of them as this year’s best actresses in sup- porting roles). Each of these folks deserves an Oscar—or perhaps two Oscars—just for putting up with my idiosyncrasies and increasingly poor memory and lack of attention to detail. Several others who didn’t work directly on the book merit special mention. My home crew—Jennifer, Patrick, and Sara—seem by now to have become inured of my book writing habits. Thanks to them for handling the bills, the moving of furniture, and the household chores while I indulged my writing habit. Finally, and emphatically, I thank my Lord and Savior, Jesus Christ, who knows my many flaws and weaknesses better than any other and never- theless patiently bears with me knowing that He—how, I don’t know—can yet make something remarkable of me. I can’t wait! Copyright ©2000 SYBEX , Inc., Alameda, CA www.sybex.com Introduction L ike many in the Linux community, you’ve probably heard of the Red Hat Certified Engineer (RHCE) program and the related RHCE exam, both of which were created by Red Hat, Inc. You may have heard that the RHCE exam is challenging, or you may have heard that it is not. You may have heard that the exam is focused on Red Hat Linux and that knowledge of Unix or a Linux distribution other than Red Hat Linux will not help you to pass the exam. Most of all, you may have wondered how RHCE certification might boost your career or, if you’re a hiring manager, whether RHCE certification could help you find qualified employees. I wrote this book to answer these questions and similar questions and to provide comprehensive material and exercises designed to prepare you to pass the RHCE exam. Is This Book for You? I f you want to learn how to administer a Red Hat Linux system, this is the book for you. In it, you’ll find clear and comprehensive explanations of the concepts you need to understand and the procedures you need to be able to perform. If you plan to take the RHCE exam, you will find this book to be even more valuable, because it focuses on the topics identified by Red Hat, Inc., as central to the RHCE exam. It contains many practice questions and exercises that will help you to prepare for and assess your readiness to take the RHCE exam. The book includes both questions and exercises because the RHCE exam has two kinds of tests: written and performance-based exams. The questions prepare you for the written part of the RHCE exam, and the exercises prepare you for the performance-based part of the exam. Once you master the questions and exercises, you will be able to approach the RHCE exam with confidence. However, the RHCE exam and this book are not for everyone. The RHCE exam is mostly a hands-on exam that attempts to assess your system administra- tion skills. This book will help you to learn and refine these skills, but unless you’ve had some experience with Unix or Linux, you probably won’t make much sense of this book or the RHCE exam. To succeed, you don’t need to be a Unix or Linux expert—although it certainly won’t hurt if you are—but you should be at least a Unix or Linux power user who has some experience in system installation and administration. If you’ve installed Linux on several systems and spent some time figuring out some system administration commands such as mount and unount, you can expect to understand the material in this book. Copyright ©2000 SYBEX , Inc., Alameda, CA www.sybex.com xxxvi Introduction What Does This Book Cover? I ’ve endeavored to cover every topic that’s important to a Red Hat Linux system administrator, especially emphasizing those topics that are likely to appear on the RHCE exam. I must write endeavored to, because those—like myself—who have taken the RHCE exam are bound by a non- disclosure agreement and cannot divulge the contents of the exam. More- over, Red Hat, Inc. regularly updates the RHCE exam with new questions and exercises. So, no program of study for the RHCE exam is or can be a substitute for real knowledge. But, this book can help you develop exactly the sort and degree of real knowledge required to pass the RHCE exam. Among the central topics covered are the following: RHCE certification and the RHCE exam A review of PC hardware, Unix, and networking that will help you fill in the gaps in what you already know Red Hat Linux installation Red Hat Linux system and network administration Network server administration X Window system administration Red Hat Linux security administration System troubleshooting and repair At the time of writing, Red Hat, Inc. had just released Red Hat Linux 6.2 and was updating the RHCE exam to reflect the new and changed features of Red Hat Linux 6.2. Thus, this book was written with Red Hat Linux 6.2 and the RHCE exam for Red Hat Linux 6.2 in mind. If you pass the RHCE exam, your certification will remain current for one year, irrespective of any new versions of Red Hat Linux released during that time. Copyright ©2000 SYBEX , Inc., Alameda, CA www.sybex.com Introduction xxxvii How Do You Take the RHCE Exam? T he RHCE exam tests your conceptual understanding of and skill in performing Red Hat Linux system administration tasks. The exam takes about seven hours, including a one-hour break for lunch. The exam is challenging: currently about one out of every three examinees fails the exam. However, proper preparation for the exam can signifi- cantly increase your likelihood of success. Red Hat, Inc., offers the RHCE exam about once a month at its Durham, NC headquarters and less frequently at its Santa Clara, California, facility. At the time of writing, Red Hat, Inc., had just announced that it will soon offer the RHCE exam in Europe and East Asia. The RHCE exam is also offered in several additional cities by Red Hat, Inc.’s training partners, including Global Knowl- edge and IBM Global Services. You can take the RHCE exam or a special four-day RHCE exam preparation course, the price of which includes the exam, which is taken the following day. The Red Hat, Inc. course numbers and the cost at the time of writing were as follows: RHCE exam only RH302 ($749) RHCE exam and preparation course RH300 ($2,498) To register for an RHCE exam or RHCE exam preparation course offered by Red Hat, Inc., at a U.S. location, call (800) 454-5502 or e-mail training@redhat.com. Also, check the following Web sites for up-to-the- minute details and additional registration information: Red Hat, Inc. www.redhat.com/services/training/training.html Global Knowledge db.globalknowledge.com/olm/go.asp?find=redhat IBM Global Services www.ibm.com/services/learning/ spotlight/linux.html Chapter 1, “Red Hat Certification,” and Chapter 31, “The RHCE Exam,” provide further information on RHCE certification and the RHCE exam. Copyright ©2000 SYBEX , Inc., Alameda, CA www.sybex.com xxxviii Introduction How to Use This Book T his book has quite a few chapters—31, to be precise. Most of the chapters are small and focused so that you can quickly find and review topics. Small chapters also help you pace your study so that you avoid burn out. A few chapters, such as the chapter on installing Red Hat Linux, are longer than most, but, generally, their length is attributable to screen shots that will help you to stay oriented to the procedures those chapters explain. So, you probably won’t find even the longer chapters overly tiring. Be sure to read the inside front cover page of this book which discusses what’s on the companion CD. Because the chapters are small, the book is organized into parts that group related chapters: Part I: Background Chapters 1–5 explain RHCE certification and review basic material on PC hardware, Unix, TCP/IP networking, and Linux. You’re probably familiar with much of this material already, so feel free to skim these chapters, using these chapters just to fill in gaps in your recollection and understanding. Part II: Installation Chapters 6–8 describe the procedure for installing Red Hat Linux, including pre-installation planning and advanced installation techniques. Part III: Configuration and Administration Chapters 9–20 describe and explain Red Hat Linux system administration, including such topics as user accounts, disk quotas, and RPM packages. Part IV: Network Services Administration Chapters 21–25 describe and explain the administration of network services. They include material on Apache, NFS, Squid, and a variety of other servers, plus material on network security and system logs. Part V: X Window System Administration Chapters 26–28 concern the X Window System, the Unix standard graphical user interface. Part VI: Network Administration Chapters 29 and 30 cover routers and firewalls. Part VII: The RHCE Exam (RH302) Chapter 31 describes the RHCE exam in detail and gives suggestions for performing well on the exam. Copyright ©2000 SYBEX , Inc., Alameda, CA www.sybex.com [...]... exam And, you’ll learn how to plan a strategy for passing the RHCE exam Red Hat Certified Engineer T his section introduces RHCE certification It briefly describes Linux, Red Hat, Inc (Red Hat) , and Red Hat Linux RHCE certification is important because Linux is one of the most powerful and popular Internet operating systems, and Red Hat Linux is the leading Linux distribution in the United States RHCEs... Inc., Alameda, CA www.sybex.com 6 Chapter 1 Red Hat Certification Sponsors may benefit from the revenue earned by offering certification training classes and certification exams They may also benefit from increased name recognition within their industry Red Hat Certified Engineer Program During 1998, Red Hat developed a certification program for Red Hat Certified Engineers (RHCE) called the RHCE program... Linux,” describes the Linux operating system in more detail Red Hat and Red Hat Linux Red Hat was founded in 1994 and provides the most popular distribution of Linux in the U.S., Red Hat Linux Its Linux distribution, like those of other vendors, includes the Linux operating system, utilities to install and maintain it, and useful applications Red Hat Linux has won many awards, including being named Infoworld’s... Alameda, CA www.sybex.com T hough the Red Hat Certified Engineer (RHCE) exam doesn’t include questions on the material presented in this chapter, it is the most important chapter in this book Here, you’ll learn about certification and Red Hat certification in particular You’ll learn about the steps you must take and the options that are available along the path to Red Hat certification You’ll learn how... SYBEX , Inc., Alameda, CA www.sybex.com Chapter 1 Red Hat Certification RHCE PREPARATION TOPICS COVERED IN THIS CHAPTER: Know and understand the benefits of certification Know and understand the significance of certification as a Red Hat Certified Engineer (RHCE) Know and understand the RHCE certification process Know and understand the content of Red Hat s certification courses Know and understand the... Because Red Hat regularly updates its Linux distribution, RHCE certification is not valid indefinitely However, according to Red Hat policy, RHCE certification remains valid for at least one year Red Hat has announced that it plans to offer a more advanced level of certification, RHCE II, focusing on server administration, networking, integration, and security RHCE II will not replace RHCE Instead, Red Hat. .. replace RHCE Instead, Red Hat expects that many candidates will use RHCE certification as a stepping stone to RHCE II certification At the time of writing, further details on RHCE II have not yet been announced by Red Hat You should check Red Hat s Web site, www.redhat.com, for the latest information on RHCE II RHCE Courses and Exam A s part of its RHCE program, Red Hat offers several courses designed... offered by Red Hat, as well as the RH302 exam The following sections help you assess your readiness to sit for the RHCE exam and help you to map out a strategy for exam success Red Hat offers courses at several locations throughout the U.S and U.K The current course schedule is available on their Web site, www.redhat.com, which also gives the current tuition for each course RH033: Introduction to Red Hat. .. useful metric of skills and knowledge Red Hat also established the RHCE program as a screening device for companies who want to partner with Red Hat These companies must have RHCEs on staff as a means of assuring that their technical staff possess the skills and experience necessary for successful collaboration with Red Hat An unusual aspect of the RHCE exam is that it is performance-based Whereas other... Inc., Alameda, CA www.sybex.com 8 Chapter 1 Red Hat Certification RH133: Red Hat Linux System Admin I, II RH133 is a four-day course intended for users who are familiar with Red Hat Linux Before taking this course, students should complete RH033 or possess equivalent experience Upon completion of the course, students should be able to install and configure Red Hat Linux, X, and various network services . from Red Hat, Inc. and not affiliated with Red Hat, Inc. in any manner. This publication may be used in assisting students to prepare for a Red Hat Certified. Certified Engineer exam. Neither Red Hat, Inc. nor SYBEX war- rants that use of this publication will ensure passing the relevant exam. Red Hat is a registered