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

The author and publisher have made their best efforts to prepare this book, and the content is based upon final release soft-
ware whenever possible. Portions of the manuscript may be based upon pre-release versions supplied by software manu-
facturer(s). The author and the publisher make no representation or warranties of any kind with regard to the completeness
or accuracy of the contents herein and accept no liability of any kind including but not limited to performance, merchant-
ability, fitness for any particular purpose, or any losses or damages of any kind caused or alleged to be caused directly or
indirectly from this book.
Manufactured in the United States of America
10 9 8 7 6 5 4 3 2 1
Copyright ©2000 SYBEX , Inc., Alameda, CA
www.sybex.com

Software License Agreement: Terms and Conditions

The media and/or any online materials accompanying this book
that are available now or in the future contain programs and/or
text files (the "Software") to be used in connection with the book.
SYBEX hereby grants to you a license to use the Software, subject
to the terms that follow. Your purchase, acceptance, or use of the
Software will constitute your acceptance of such terms.
The Software compilation is the property of SYBEX
unless otherwise indicated and is protected by copyright
to SYBEX or other copyright owner(s) as indicated in the
media files (the "Owner(s)"). You are hereby granted a
single-user license to use the Software for your personal,
noncommercial use only. You may not reproduce, sell,
distribute, publish, circulate, or commercially exploit the
Software, or any portion thereof, without the written
consent of SYBEX and the specific copyright owner(s) of
any component software included on this media.
In the event that the Software or components include specific

defects for a period of ninety (90) days after purchase. The
Software is not available from SYBEX in any other form or
media than that enclosed herein or posted to www.sybex.com.
If you discover a defect in the media during this warranty
period, you may obtain a replacement of identical format at no
charge by sending the defective media, postage prepaid, with
proof of purchase to:

SYBEX Inc.
Customer Service Department
1151 Marina Village Parkway
Alameda, CA 94501
(510) 523-8233
Fax: (510) 523-2373
e-mail:
WEB: HTTP://WWW.SYBEX.COM
After the 90-day period, you can obtain replacement media
of identical format by sending us the defective disk, proof of
purchase, and a check or money order for $10, payable to
SYBEX.

Disclaimer

SYBEX makes no warranty or representation, either
expressed or implied, with respect to the Software or its
contents, quality, performance, merchantability, or fitness
for a particular purpose. In no event will SYBEX, its dis-
tributors, or dealers be liable to you or any other party for
direct, indirect, special, incidental, consequential, or other
damages arising out of the use of or inability to use the

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

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.

’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

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

3.
Complete the exercises in the chapter. Bear in mind that the RHCE exam
will require you to demonstrate skills, which are acquired only by prac-
tice, not by precept. The exercises are probably the closest experience to
a real RHCE exam you’ll find anywhere. They’re worth doing, if you plan
to pass the exam.
4.
Answer the review questions at the end of the chapter. These questions
closely resemble the experience of the written portion of the RHCE exam.
5.
Review chapter topics related to any questions you missed. Be sure
you know the right answer and why the other responses are wrong.
6.
Work your way through the entire book in this fashion, one chapter at
a time.
7.
When you believe you’re ready, take the practice exam in Appendix A,
then assess your performance.
8.
Take the bonus exam included on the CD to further test your readi-
ness for the real thing. If you do well, sign up for the RHCE exam or
the RHCE preparation course, according to your preference. If you
don’t do well, repeat steps 1–8 until you’re able to pass the practice
exam with confidence.
9.
Use the Flashcard questions on the CD that accompanies this book to
stay sharp while awaiting the RHCE exam.
Copyright ©2000 SYBEX , Inc., Alameda, CA
www.sybex.com
Assessment Test

RIP-2
4.
To check permission of the local host to access the X server running on
server, which of the following commands should be issued?
A.
export DISPLAY=server:0.0
xhost
B.
export DISPLAY=server:0.0
xhost +
C.
export DISPLAY=server:0.0
xhosts
D.
export DISPLAY=server:0.0
xhosts +
Copyright ©2000 SYBEX , Inc., Alameda, CA
www.sybex.com
xlii Assessment Test
5.
Which of the following programs is used to configure the system time zone?
A.
timeconfig
B.
timezone
C.
timezoneconfig
D.
zoneconfig
6.

D.
mkinitrd /boot/initrd-version.img version
Copyright ©2000 SYBEX , Inc., Alameda, CA
www.sybex.com
Assessment Test xliii
9.
Quotas are supported on which of the following file system types?
A.
dos
B.
ext2
C.
iso9660
D.
vfat
10.
Which of the following files specifies a user’s window manager?
A.
~/.wm_style
B.
~/.wmanager
C.
~/.Xclients
D.
~/.Xsession
11.
Which of the following are Red Hat Linux installation types?
A.
Expert
B.

A.
22
B.
25
C.
50
D.
110
15.
To determine whether a Linux kernel supports firewalling, you should
check for the existence of which of the following files?
A.
/proc/net/ip_always_defrag
B.
/proc/net/ip_fwchains
C.
/proc/sys/net/ipv4/ip_always_defrag
D.
/proc/sys/net/ipv4/ip_fwchains
16.
To masquerade packets originating from a local protected network,
which of the following ipchains commands should be specified?
A.
ipchains –A forward –i eth0 \
–s 192.168.1.0/24 –j MASQ
B.
ipchains –A input –i eth0 \
–s 192.168.1.0/24 –j MASQ
C.
ipchains –A local –i eth0 \

/lib/2.2.15
B.
/lib/modules/2.2.15-2
C.
/modules/2.2.15
D.
/modules/2.2.15-2
20.
Which of the following is the final operation performed by
rc.sysinit?
A.
Activate swap partitions.
B.
Load the keymap.
C.
Set the logging level.
D.
Store the boot messages.
21.
Which of the following logging configuration file entries will log messages
pertaining to FTP logins that have a critical priority?
A.
auth.alert: /var/log/messages
B.
auth.err: /var/log/messages
C.
auth.info: /var/log/messages
D.
auth.*: /var/log/messages
Copyright ©2000 SYBEX , Inc., Alameda, CA

mount -t ext2 /dev/hda1 / -o defaults,rw
C.
mount -t ext2 /dev/hda1 / \
-o defaults,remount,ro
D.
mount -t ext2 /dev/hda1 / \
-o defaults,remount,rw
25.
Which of the following commands will halt the system?
A.
init 0
B.
halt
C.
shutdown -h now
D.
telinit 0
Copyright ©2000 SYBEX , Inc., Alameda, CA
www.sybex.com
Assessment Test xlvii
26.
Which of the following allow you to run Windows 9x under Linux?
A.
You can configure the system for multi-boot operation.
B.
You can install LILO.
C.
You can install VMware.
D.
You can install WINE.

C.
PPP users
D.
SLIP users
30.
Which of the following files establishes the user’s path?
A.
/etc/bashrc
B.
/etc/profile
C.
~/.bashrc
D.
~/.bash_profile
Copyright ©2000 SYBEX , Inc., Alameda, CA
www.sybex.com
xlviii Assessment Test
31.
Which of the following correctly pairs a virtual console with its installation
program function?
A.
2, shell prompt
B.
3, install program messages
C.
4, system messages
D.
5, other messages
32.
Which program is used by the installation procedure to configure X?

Which of the following programs is not PAM-aware?
A.
ftp
B.
login
C.
rlogin
D.
telnet
Copyright ©2000 SYBEX , Inc., Alameda, CA
www.sybex.com
Assessment Test xlix
36.
To permit a client host to access a printer remotely, the client host can
be listed in:
A.
/etc/hosts
B.
/etc/hosts.equiv
C.
/etc/hosts.lpd
D.
/etc/printcap
37.
Which of the following correctly specifies the location of a compiled
Linux kernel?
A.
/usr/src/linux/arch/i386/boot/bzImage
B.
/usr/src/linux/arch/i386/boot/kernel

ld.so
C.
ldconfig
D.
ldd
Copyright ©2000 SYBEX , Inc., Alameda, CA
www.sybex.com
l Assessment Test
41.
Which of the following commands is included in the standard rescue
mode complement of commands?
A.
kill
B.
pico
C.
sync
D.
vi
42.
Which of the following is true of the Red Hat Linux text mode instal-
lation procedure?
A.
It is easier for beginners to use than the graphical mode installation
procedure.
B.
It is faster than the graphical mode installation procedure.
C.
It is more reliable than the graphical mode installation procedure.
D.

B.
Install packages after installation.
C.
Select the desired components.
D.
Select the desired packages.
46.
The dynamic loader’s cache resides in which of the following files?
A.
/etc/ld.so.cache
B.
/etc/ld.so.conf
C.
/lib/ld.so.cache
D.
/lib/ld.so.cache
47.
To use Xconfigurator noninteractively, where possible, you should
invoke the program with which of the following flags?
A.
--auto
B.
--expert
C.
--kickstart
D.
--probe
48.
You can damage a monitor by running which of the following tools?
A.

D.
make dep clean bzImage modules
Copyright ©2000 SYBEX , Inc., Alameda, CA
www.sybex.com
Answers to Assessment Test liii
Answers to Assessment Test
1.
C. The keep line specifies that path information in /etc/
conf.modules supplements default information. See Chapter 17 for
more information.
2.
A, B. Linux, sometimes called GNU/Linux, is the combination of Tor-
valds’s kernel and the GNU utilities and programs. See Chapter 5 for
more information.
3.
A. OSPF-2 and RIP-2 are interior protocols. EGP is no longer popular.
See Chapter 29 for more information.
4.
A. Without arguments, the xhost command can be run on a client or
server. See Chapter 28 for more information.
5.
A. The timeconfig program configures the time zone. See Chapter 9
for more information.
6.
B. Runlevel 1 is single-user mode. Runlevel 3 is multi-user mode with net-
working. Runlevel 4 is essentially the same as runlevel 3. See Chapter 9
for more information.
7.
D. You cannot conveniently convert to MD5 password encryption; it
must be specified during installation. See Chapter 9 for more information.

chain. See Chapter 30 for more information.
17.
B, D. The IP address 192.168.1.0/24 has a 24-bit network address and
8-bit host address. The netmask 255.255.255.0 has 24 1 bits, indicat-
ing a 24-bit network address. See Chapter 4 for more information.
18.
A. The ping command is sometimes issued by ordinary users and
therefore must reside in /bin rather than /sbin. It is an essential trou-
bleshooting tool and therefore resides in /bin rather than /usr/bin.
See Chapter 13 for additional information.
19.
B. The modules reside in a subdirectory of /lib/modules and are
named for the kernel version and build with which they’re associated.
See Chapter 13 for additional information.
20.
D. The boot messages are stored as the last operation, so that no mes-
sages are lost. See Chapter 14 for more information.
21.
B, C, D. The crit priority is higher than those of err and info, but
lower than that of alert. The * priority matches all message priorities.
See Chapter 24 for more information.
22.
C. Virtual console 7 is associated with X. See Chapter 27 for more
information.
23.
B. The flag is level, not levels, and the on argument is required. See
Chapter 14 for more information.
24.
D. The remount option lets you remount a mounted file system. See
Chapter 15 for additional information.