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Emmett Dulaney

01 Apr 2005

As Novell has come to embrace Linux in its product line, marketing and strategy, it has also come to support--if not flat-out endorse--the certifications from the Linux Professional Institute (LPI). Various Novell certifications now require Level 1 and/or Level 2 certifications from LPI to show you know and understand the basics of Linux administration. Let's look at what the LPI certifications are and then focus on one of the key exams you must pass to become certified. (For more information on LPI, visit www.lpi.org.)

What Are LPI Certifications?

The Linux Professional Institute currently has two levels of Linux certification with plans for more in the future. To become certified at any level, you must pass two exams and you must certify at the first level before you can certify at the second level. To certify at Level 1 (Junior-level Administrator), you must pass exams 101 and 102. You must pass exams 201 and 202 to certify at Level 2 (Intermediate-level Administrator).

The exams consist of both multiple-choice and fill-in-the-blank questions and are focused on generic, vendor-neutral Linux. In other words, the topics covered by the certification test apply to any flavor of Linux whether you are using SUSE LINUX, Red Hat or any other Linux implementation. To achieve this vendor-neutrality, the questions typically focus on the lowest common denominator in all implementations, for example, the chown utility, and not focus on tools that exist only in one distribution, such as YaST in SUSE LINUX.

Most of the fill-in-the-blank questions relate to commands and syntax so experience giving those commands on a live system becomes essential to answering correctly. You must be very familiar with Linux administration before considering taking these exams.

Not all of the topics on the exams are evenly weighted. You should study every topic and be comfortable with it, but if you find yourself in a pinch, take weighting into account and focus your study time accordingly. While not exact, think of the weighting as percentages.

The LPI certifications are highly regarded, not only by Novell, but also by the Linux community as a whole. Unfortunately, there is not a lot of current, up-to-date, study material available for the exams. When the LPI certification first went live in XXXX, several publishers had books covering the 101 and 102 exams, while none (to my knowledge) did on exams 201 and 202. After the Level 1 exams were updated, few publishers updated their existing books to reflect the new material.

This article focuses on exam 101 and what you must know to pass it. In the future, we'll try to cover exam 102 to round out what you must know to pass both exams and become certified at Level 1.

The Topics

As mentioned, when studying for the exam, take weighting into account. Weighting the topics breaks them down in differing significances:

GNU & Unix Commands: 31 (See Tables 2-10.)
Linux Installation & Package Management: 30 (See Table 11.)
Devices, Linux Filesystems and Filesystem Hierarchy Standard: 24 (See Devices, Linux Filesystems and Filesystem Hierarchy Standard below and Table 12.)
The X Window System: 13 (See Table 13.)
Hardware & Architecture: 8 (See Table 14.)
NOTE The numbers add to 106 rather than to 100 because there is not an exact correlation between the weighting and percentages.

If you want to break down the areas to study even further, look at the weighting of each objective and organize them by the most important. (See Table 1.) Knowing what to study--what the creator of the exam considers the most important--and then being comfortable with those topics is invaluable to acing an exam.

Table 1: Weighting Each Exam Objective

Objective	Topic Area	Weight
Use Debian package management	Linux Installation & Package Management	8
Use Red Hat Package Manager(RPM)	Linux Installation & Package Management	8
Process text streams using filters	GNU & Unix Commands	6
Find system files and place files in the correct location	Devices, Linux Filesystems and Filesystem Hierarchy Standard	5
Install and configure Xfree86	The X Window System	5
Design hard disk layout	Linux Installation & Package Management	5
Make and install programs from source	Linux Installation & Package Management	5
Work on the command line	GNU & Unix Commands	5
Use streams, pipes and redirects	GNU & Unix Commands	5
Create, monitor and kill processes	GNU & Unix Commands	5
Use file permissions to control access to files	Devices, Linux Filesystems and Filesystem Hierarchy Standard	5
Install and customize a Window Manager Environment	The X Window System	5
Perform basic file management	GNU & Unix Commands	3
Modify process execution priorities	GNU & Unix Commands	3
Search text files using regular expressions	GNU & Unix Commands	3
Set up different PC expansion cards	Hardware & Architecture	3
Manage shared libraries	Linux Installation & Package Management	3
Create partitions and filesystems	Devices, Linux Filesystems and Filesystem Hierarchy Standard	3
Maintain the integrity of filesystems	Devices, Linux Filesystems and Filesystem Hierarchy Standard	3
Control mounting and unmounting filesystems	Devices, Linux Filesystems and Filesystem Hierarchy Standard	3
Managing disk quota	Devices, Linux Filesystems and Filesystem Hierarchy Standard	3
Set up a display manager	The X Window System	3
Configure Fundamental BIOS Settings	Hardware & Architecture	1
Configure Modem and Sound cards	Hardware & Architecture	1
Set up SCSI devices	Hardware & Architecture	1
Configure Communication Devices	Hardware & Architecture	1
Configure USB devices	Hardware & Architecture	1
Install a boot manager	Linux Installation & Package Management	1
Perform basic file editing operations using vi	GNU & Unix Commands	1
Manage file ownership	Devices, Linux Filesystems and Filesystem Hierarchy Standard	1
Create and change hard and symbolic links	Devices, Linux Filesystems and Filesystem Hierarchy Standard	1

Not all of the topics on the exams are evenly weighted.

Table 2: GNU & UNIX Commands

Utility	Default Purpose
&	Start a process in the background
bg	Move a job to the background
cat	Display the contents of a file
cd	Change from the current directory to another
cp	Copy a file or directory
cut	Extract a field from each line of a file
dd	Copy files between media
egrep	Originally combined features of grep and fgrep with new possibilities; can now be emulated with grep -E
fg	Move a job to the foreground
fgrep	Originally offered features not found in grep, but can now be emulated with grep -F
find	Locate a file based on given criteria
fmt	Format the output to fit the desired display
grep	Displays lines that contain the given string
head	Display the beginning lines of a file
jobs	Display a list of jobs running in the background
join	Combine columns from two files into a single display
kill	End a process
killall	End several processes
ls	List files and directories on the system
man	Display the manual pages for a command, utility or file
mkdir	Make directories
mv	Rename/move a file or directory
nice	Start a process at a priority other than the default
nl	Number the lines of a file
paste	Put the contents of two files in a single display
ps	Show the running processes
pstree	Graphically depict the relationship between processes
pwd	Display the current directory (always in absolute format)
renice	Change the priority of a running process
rm	Remove files and directories
rmdir	Remove empty directories
sed	Allows text to be changed before being displayed
sort	Sort the lines of the file
stty	Show the settings for the terminal
tac	Display the contents of a file in reverse order
tail	Display the last lines of a file
tee	Send output to default and to a file
top	Show and monitor system information and processes
touch	Change the times associated with a file
tr	Translate one set of characters into another
wait	Suspend further processing until another process completes
wc	Count the number of words, lines and characters/bytes within a file
xargs	Pass the output of one command into another

Table 3: Metacharacters and Their Purposes

Metacharacter	Purpose
' '	Cancel the special meaning of anything but the backquote (everything except the backquote?)
" "	Cancel the special meaning of most characters
$	Treat the next string as a variable
$()	Allow a command to be treated as a variable
*	The wildcard for any number of characters
;	Separate dissimilar commands
?	Any single character
[ ]	Any of the enclosed characters
\	Treat the next character literally
` `	Execute the enclosed command
\|	Allow one command's output to be the next command's input
<	Input redirection
<<	"Here"
>	Output redirection
>>	Output append

Table 4: Navigation Keys for the vi Editor

Key	Result
-	Move to the first character of the previous line
$	Move to the last position of the current line
(	Move backward one sentence
)	Move forward one sentence
{	Move to the beginning of the previous paragraph
}	Move to the beginning of the next paragraph
^	Move to the first character of the current line (ignoring spaces)
+	Move to the first character of the next line
0	Move to the beginning of the current line
b	Move backward to the beginning of the previous word
B	Move backward to the beginning of the previous word, ignoring symbols and punctuation
E	Move to the end of the next word
E	Move to the end of the next word, ignoring symbols and punctuation
Enter\Return	Move to the beginning of the next line
H	Move left one space
J	Move down one line
K	Move up one line
L	Move right one space
W	Move to the beginning of the next word
W	Move to the beginning of the next word, ignoring symbols and punctuation
G	Move to the last line of the file
xG	"Goto" line number x

Table 5: Available vi "Change Text" Combinations

Keystroke	Result
C$	Change from here to the end of the line
c)	Change from here to the end of the sentence
c^	Change from here to the beginning of the line
c}	Change the remainder of the paragraph
3cw	Change the next three words
r	Replace an individual character
R	Go to "Replace" mode and overwrite existing text with new text

Table 6: Ways to Save a File in the vi Editor

Keystroke	Result
:.,12w newfile	Saves lines from where the cursor currently is to line 12 in a file named newfile
:2, 5w newfile	Saves lines 2 thru 5 in a file named newfile
:12, $w newfile	Saves lines from 12 to the end of the file in a file named newfile

Table 7: Keys Associated with Input Mode in the vi Editor

Keystroke	Result
a	Inserts text after cursor (append)
A	Inserts text at the end of the current line
i	Inserts text before cursor
o	Opens a new line below the cursor
O	Opens a new line above the cursor
s	Removes the current letter and places you in insert mode. This is known as the "substitute" command
S	Substitute mode for the whole line

Table 8: Deletion Keystrokes in the vi Editor

Keystroke	Result
d$	Deletes from the cursor position to the end of the line
d)	Deletes the remainder of the sentence
d}	Deletes the remainder of the paragraph
d0	Deletes from the cursor position to the beginning of the line
db	Deletes the previous word
dl	Deletes a letter
7dl	Deletes seven letters
dw	Deletes a word
7dw	Deletes four words (dw not only deletes the word, but also deletes the space after the word. To delete only to the end of a word, use de instead.)

Table 9: Screen Navigation Keystrokes in the vi Editor

Keystroke	Result
Ctrl+F	Move forward one screen
Ctrl+B	Move backward one screen
Ctrl+D	Move forward one-half screen
Ctrl+U	Move backward one-half screen
Ctrl+E	Scroll the screen up one line
Ctrl+Y	Scroll the screen down one line
H	Move to the top line of the screen
L	Move to the last line of the screen
M	Move to the middle line of the screen

Table 10: Keystroke to Copy Text in the vi Editor

Keystroke	Result
Y$	Yanks from here to the end of the line
y)	Yanks the remainder of the sentence
Y}	Yanks the remainder of the paragraph
Y0	Yanks from here to the beginning of the line
yb	Yanks the previous word or part of a word
yl	Yanks a single letter
7yl	Yanks the next seven letters
yw	Yanks a single word
7yw	Yanks the next seven words
yy	Yanks an entire line
7yy	Yanks seven lines
Y	The same as y$

Table 11: Managing Packages and Configuring Linux Installation Parameters

Utility	Default Purpose
bzip2/bunzip2	Compress/uncompress files
depmod	Determine module dependencies
dmesg	Print out the boot-up messages
dpkg	Debian package manager
grub	Linux boot loader
gzip	Compress files
gunzip	Uncompress files
halt, shutdown, reboot	Interfaces to shutdown
init	Change the runlevel
insmod	Install a module
last	View the most recent entries in the wtmp file
ldconfig	Updates and maintains the cache of shared library data and symbols for the dynamic linker.
ldd	List which shared libraries a program depends on
lilo	Configure the Linux Loader
lsmod	List the loaded modules
modinfo	Print information about a module
modprobe	Probe and install a module and its dependents
rmmod	Remove a module
rpm	Red Hat Package manager
runlevel	Show the current runlevel of the system
tar	Create and extract files known as tarballs
telinit	Same as init

Table 12: Commands and Concepts for Managing Filesystems

Utility	Default Purpose
chgrp	Change an entity's group association
chmod	Change an entity's permissions
df	See the amount of free disk space
du	See disk usage statistics
edquota	Create quotas for users or groups
fdisk	Partition the disk and work with the partition table
fsck	Check the file system status
locate	Find a file from the locatedb database
lspci	Shows information about the PCI buses
mke2fs	Create a Linux Extended-2 filesystem (ext2)
mkfs	Create a filesystem
mkreiserfs	Create a Reiser filesystem
mount	Mount a filesystem
quotaoff	Turn off user/group quotas
quotaon	Turn on user/group quotas
repquota, quota, quotacheck, and quotastats	View quota usage
SGID	Set the group ID when running a file
Sticky bit SUID	Change the operation of files and directories Set the user ID when running a file
umask	A numerical variable subtracted from the default permissions when creating new files and directories
umount	Unmount a filesystem
updatedb	Update the locatedb database
whereis	List all information about locations associated with a file
which	Find a file from the path statement

Table 13: X Window System Utilities and Concepts

Utility	Purpose
fvwm	Popular virtual desktop window manager
kdm	KDE display manager
mwm	Motif Window Manager
startx	shell script to start the X environment
X	X server
Xconfigurator	X configuration tool
Xdm	X display Manager
XF65Setup	X configuration tool
Xf86config	X configuration tool
xinit	Configure and start the X server
xinstall.sh	X installation program
xload	X client
xsetroot	Manage the root window
xterm	Terminal emulator

Table 14: Hardware and Architecture Utilities

Utility	Purpose
chat	program used to perform the chat script negotiation during a ppp session
date	check and set the system date
lspci	Lists all devices connected through the PCI bus
minicom	terminal emulation program
pppd	program to establish a PPP connection to a remote system
setserial	check and set the serial port parameters
sndconfig	configure a sound card
timeconfig	configure the system timezones

Devices, Linux Filesystems and Filesystem Hierarchy Standard

During installation, Linux creates a number of directories which hold system files. Under any normal installation, regardless of the vendor, the folder structure includes the directories as they adhere to the Filesystem Hierarchy Standard (FHS).

/ (root) Everything begins at the root directory (/). This is the beginning directory of which everything else becomes a subdirectory, or subcomponent beneath the root directory. When specifying locations and using absolute addressing, always start with the root directory; it is impossible to go back any further.

bin The /bin directory holds the binaries (executables) that are essential to using the Linux operating system. Many of the utilities discussed thus far are located in the bin directory, including:

cat
cp
date
dd
gzip
ls
mkdir
mv
ps
rm
sed
vi

boot The /boot directory houses the files needed to boot the system, minus configuration files, as well as the kernel. In some implementations, the kernel is stored in the / directory (a holdover from the days of Unix), but in most newer versions, /boot is used. This directory contains all the files needed to boot (including the kernel) except the configuration files.

dev The /dev directory holds the device definitions. You can drag a file to a graphical icon of the floppy drive on the desktop because a definition for the floppy drive is held in the /dev directory. A definition file is associated with every device, whether it is a terminal, drive, driver and so on. You should know that the following types of files exist in Linux:

Normal Files: files that contain data used by users or applications

Directories: containers that hold files or other directories

Device Files: one device file exists for each physical device

Links: pointers to other files

Sockets: files used to exchange data between two running processes

Pipes (also known as FIFOs for First In, First Out): Like sockets, they are used to exchange data, but the data is queued and can only flow one way

etc In everyday language, "etc." is used to mean "and so on." In the Linux world, however, the /etc directory holds configuration files and samples that are specific to the machine. For example, ABC Corporation and DEF Corporation can both install the same version of Linux on Intel-based machines at their sites. When they do, both will have root directories, both will have /bin directories with matching sets of utilities in them, and so on. One major difference between the two machines will be the values that can be found in the /etc directory. The users who log on at ABC are not the same as those who can log on at DEF; thus, user accounts are stored in /etc. The groups are not the same at the two organizations; again, those related files are stored here.

home The /home directory holds subdirectories that are the home directories for users. For example, user edulaney, when entering the cd command, will be placed in /home/edulaney providing that variable (the default) is used when setting up the account. Each user's home directory provides him a location where he can store files, as well as where individual configuration files are found and accessed. Some services, such as ftp and http, also create directories beneath /home. Files that are used to configure the environment for the user, such as .profile, .bashrc, and .bash_history are stored in the home directories.

lib Shared library files needed by binaries, such as those in the /bin directory, are located in the /lib directory and subdirectories beneath it. Generally, the libraries comprise executables written in the C language.

media The /media directory is used for mounting removable media. Two subdirectories are created here by default: cdrom and floppy. Folders for other devices, such as dvd, dvdrecorder or cdrecorder, may also appear if they are installed.

mnt The /mnt directory holds external filesystems that are mounted. The entities that appear in this directory are never on this filesystem, but rather external resources that can be linked to and accessed from here. The external resources can be other filesystems or devices. The devices appear as directories with common names. The /mnt/tmp subdirectory here is intended to hold temporary files, but it's preferable to use the /tmp. External filesystems are loaded, and thus appear, beneath this directory with the mount command. They are removed with the umount command.

opt The /opt directory holds optional (add-in) application software. Not all applications are installed here, but when they are, they create a subdirectory for their variables using the application name.

proc The /proc directory is the virtual filesystem. It is dynamically generated and updated and holds information about processes, the kernel and related system information. Processes are depicted as folders, each having permissions and variables associated with it. Other system information is most commonly depicted as files.

root The /root directory is the home directory for the root user. For security purposes, it is beneath the / directory rather than being a subdirectory of /home. For true security, it is further recommended that you move this directory to another location and rename it to a less obvious (and inviting) name.

sbin Just as the /bin directory holds standard executables that most users utilize, the /sbin directory holds binary executables for system administration. Many of these utilities are used for booting the system and once resided beneath the /etc directory. The following are some of the files located beneath this directory:

dump
fdisk
fsck
halt
ifconfig
init
mkfs
poweroff
reboot
shutdown

srv The /srv directory holds the files for the services that are available on the server--each in a separate subdirectory.

tmp As the name implies, the /tmp directory holds temporary files. Only short-term files should be placed here because many systems clean (delete) all entries in this directory on either startup or shutdown. Examples of files that exist beneath /tmp are shadow copies of files opened for editing, any application's temporary files (stored between operations) and so on.

usr Originally an acronym for "user-specific resources," /usr is now an enormous directory with a large number of subdirectories. Subdirectories beginning with X are used to define the X Windows environment. The /bin subdirectory, as has been the case each time the same name has been encountered, contains user binary (executable) files. The files placed here include:

cut
diff
file
grep
killall
nl
passwd
wc

var Short for variable, the data contained beneath this directory fluctuates in nature. Typically, many subdirectories here hold dynamic files, such as spools and logs. The main directories to know among these variables are:

lock: holds locked files

log: used for log files such as those created by login and logout (wtmp), who is currently using the system (utmp), and those for mail, the spooler, etc.

run: files needed for the runlevel

spool: spooled data waiting for processing (such as printing)

Other directories Other directories can be created and exist beneath the / directory. Those listed in the preceding sections are always present and the following two directories might also be present:

install: holds information about the installation, such as scripts, errors, etc.

lost+found: On a perfect system, this directory should be empty. When corruption occurs, however, the results are placed in this directory.

(For more information about the Filesystem Hierarchy Standard, visit www.pathname.com.)

Summary

This article introduced the LPI certifications and looked at the topics on the first exam you must pass in order to become certified as a Junior-level Administrator. Look for another article covering the topics you must pass on exam 102--the second test you must pass to become certified at Level 1.

For more information on lpi certifications, visit www.lpi.org

* Originally published in Novell Connection Magazine

Disclaimer

The origin of this information may be internal or external to Novell. While Novell makes all reasonable efforts to verify this information, Novell does not make explicit or implied claims to its validity.