Handle With Linux

The LPI certification is a valuable certification for Linux system administrators. LPI has partnered with Novell and now the certification has become even more valuable as it's also a Novell certification by now which means you get 2 certifications at once. The LPIC 1 certification is also the base for the ubuntu certified professional certification. So if you like to become a linux all-round certified administrator. This is probably one of the best (and cheapest) choices.

This is the first article in a series of tutorials, which will try to help you prepare for the LPI certification exam.

The LPI certification consists of 3 levels for which you need to pass multiple exams each.
I will begin writing this series about the first objective of the first exam

from the LPI website:

Objectives: Exam 101
Topic 101: System Architecture
101.1 Determine and configure hardware settings
Weight
2
Description
Candidates should be able to determine and configure fundamental system hardware.
Key Knowledge Areas
Enable and disable integrated peripherals.
Configure systems with or without external peripherals such as keyboards.
Differentiate between the various types of mass storage devices.
Set the correct hardware ID for different devices, especially the boot device.
Know the differences between coldplug and hotplug devices.
Determine hardware resources for devices.
Tools and utilities to list various hardware information (e.g. lsusb, lspci, etc.)
Tools and utilities to manipulate USB devices
Conceptual understanding of sysfs, udev, hald, dbus
The following is a partial list of the used files, terms and utilities:
/sys
/proc
/dev
modprobe
lsmod
lspci
lsusb

/proc

/proc is the mount point for the process file system which consists of a pseudo file system used to access kernel process information.

The proc directory therefore contains a directory for every running process and a set of files which can be read to obtain current hardware information.

For instance by examining the contents of the /proc/interrupts file we can obtain information about the current IRQ's (kernel interrupts) which are in use.

# cat /proc/interrupts
CPU0 CPU1 CPU2 CPU3
0: 22780 22747 22308 22355 IO-APIC-edge timer
1: 0 1 0 1 IO-APIC-edge i8042
2: 0 0 0 0 XT-PIC-XT cascade
6: 0 1 1 1 IO-APIC-edge floppy
7: 0 0 0 0 IO-APIC-edge parport0
8: 2 0 2 1 IO-APIC-edge rtc0
12: 3 0 0 1 IO-APIC-edge i8042
14: 16 18 16 20 IO-APIC-edge ide0
16: 0 0 0 0 IO-APIC-fasteoi uhci_hcd:usb4
17: 13 14 13 12 IO-APIC-fasteoi uhci_hcd:usb1, ehci_hcd:usb5
18: 0 0 0 0 IO-APIC-fasteoi uhci_hcd:usb3
19: 299863080 299965769 299946148 299891811 IO-APIC-fasteoi uhci_hcd:usb2, ata_piix
219: 176615287 176512540 176532601 176586888 PCI-MSI-edge eth0
NMI: 0 0 0 0 Non-maskable interrupts
LOC: 927890443 1124337444 772712819 742489394 Local timer interrupts
RES: 61560865 63586013 55218931 55718672 Rescheduling interrupts
CAL: 181626 180454 178183 179707 function call interrupts
TLB: 8433844 8025690 10248451 10167195 TLB shootdowns
TRM: 0 0 0 0 Thermal event interrupts
SPU: 0 0 0 0 Spurious interrupts
ERR: 0
MIS: 0

read up on procfs on wikipedia: http://en.wikipedia.org/wiki/Procfs

and on IRQ's : http://en.wikipedia.org/wiki/Interrupt_request

/sys

The sys filesystem is in use since the 2.6 kernel it's a bit like the /proc filesystem as it's also a virtual file system. In the sys filesystem, each device which exists on your system has it's own directory which contains files showing the resources allocated to it.

Exploring this directory yourself and using cat to show file contents will teach you a lot about it.

/dev

The /dev directory contains file system entries which represent devices that are attached to the system.
I'll go in to this in detail in a following article.

lspci

lspci shows you information about the pci devices on your system, read the man pages for more information about this command.

$ man lspci

I don't believe you need to know uncommon options for this command to answer any questions on the exam. You do need to know what it's for and also try to remember which information it does/doesn't display.

lsusb

from the man page:
lsusb is a utility for displaying information about USB buses in the system and the devices connected to them.
To make use of all the features of this program, you need to have a Linux kernel which supports the /proc/bus/usb interface (e.g., Linux kernel 2.3.15 or newer).

Same goes for lsusb, read the man page, try to remember what it does and what it does not show.
The part about the kernel version is important to remember, LPI loves questions about which kernel version you need for what functionality.

lsmod

from the manpage:
lsmod is a trivial program which nicely formats the contents of the /proc/modules, showing what kernel modules are currently loaded.

Remember: ls means list and that's what these three commands do. And also try to remember you can retrieve the same information by using $cat /proc/modules

modprobe

Do read the manpage for modprobe, and learn the description. Remember /etc/modprobe.conf and /etc/modprobe.d configuration file and directory.
There's a pretty big change you'll get a question about modprobe on your exam.

The rest of the knowledge areas for this objective will be covered in a following article.

Practice exam questions on this site!

I've put up a quiz on the site which has 25 random chosen questions to test your level of knowledge. They are chosen random from a pool of questions. The difficulty level and material covered is that of the LPIC 101 exam. If there's demand I'll put up more questions and other exam levels.

Register for free and try your skill level:
(don't worry if you don't have enough time to finish, the test will resume where you left of when you come back.)
LPIC level 1 exam practice

(Also nice to do if you just like to know if you could make it)

UPDATE: improved registration captcha, excuse for those of you who couldn't pass it.

added the Level 1 second exam (lpic 102):
LPIC level 2 exam practice

UPDATE: 15 random practice questions about proc available: (more in the future)

proc practice test (hard)