Archive for April, 2010
Certifiable: Preparing for the LPIC Level 1 Certification – Part 2
Posted by RossB in Articles, Certifiable Series, Exam Details on 2010/04/30
Certifiable is a series dedicated to helping you get ready to take the LPIC 1 exams, both in mental state and how to study and experiment more effectively.
In Part 1 of the Certifiable Series we discussed studying for your LPIC, how to succeed and how to fail.
How Ready are You for the Exams?
How ready are you to take and pass the LPI Level 1 exams? This article is designed to give you an inside view of many details that often escape examinees until they’ve taken their first exam, win or lose. Every bit of advance information that can be conveyed to you will help reduce your stress, dispel the unknown and make you that much more likely to succeed in passing your exam.
The Exams
You will be taking two exams as a part of this certification: the 117-101 and 117-102. In older previous versions of the exams you had two choices for the first exam: 117-101 RPM and 117-101 DPKG. The two 101 exams were identical, except that the RPM exam covers the RPM package style, whereas the DPKG exam focuses on Debian’s .deb packaging style.
Now we’re back to two exams, 101 and 102, with topic 102 of exam 101 being Linux Installation and Package Management, containing both the RPM and DPKG packaging styles, as well as adding the YUM package management style.
Sections and Weights
The exam’s are broken up into sections, 101-104 for the first (101) exam, and 105-110 for the second (102) exam, (see below). Each section contains multiple sub-sections, such as GNU and Unix Commands containing 103.1 Work on the command line and 103.3 Perform basic file management, among many others. Each sub-section’s contents are assigned question weights.
Note: Weights on an exam topic denote how many questions are likely to appear on the exam, not how much is scored for each question.
The table below shows the main section numbers, names and weights for reference.
It’s good to know the breakdown of sections and questions for the exams before you take them. This information is not proprietary; it’s just something you don’t typically see unless you take the exams or do extensive research with the LPI Objectives Wiki.
Taking the Actual Exams
The LPIC exams are all 90 minutes in length. A reminder of this time amount is the ticking clock on the screen that lets you know how much time is left before they kick you out of the exam, or you’re done.
Both of the major testing vendors use similarly functioning systems, so anywhere you take the LPIC exams will have the same methodology of exam generation. LPIC exams are randomly generated at the time of registration and then downloaded to the testing center on the day of testing. Each and every exam is randomly generated, with the questions doled out based on the weights and section. If, by chance, two people register at the same time, they might get vaguely similar exams, but it should be noted that even between the two exams the order of the questions and the order of the answers for the questions will be randomized. It’s extremely unlikely that two examinees will get an identical exam or get the same exam mix and questions for a retake. Don’t bother trying to figure out what will appear the next time; be sure to look at the second sheet of your test results and study further for the sections you didn’t do well on.
Taking the exam is quite an adventure, and it involves real thinking as well as skill and time management. This series shows you what to expect and how to deal with the potential problems, puzzles, and predicaments you are likely to encounter.
Beta Questions
Warning: Exams can contain a number of beta questions, making them longer and adding additional time to compensate for those questions. Many examinees are somewhat taken aback by this practice, and I’m not a fan of experimenting on the paying customers in this way, but it’s a fact of life and you should be prepared for it. These beta questions are being vetted, measured for how many people pass or fail each one and then normalize later for inclusion into future exam question pools.
LPI does not let you know beforehand if you’re taking an exam containing beta questions, you just find out when you sign in and start taking the exam. If the number of exam questions is greater than the total of the question weights for that exam’s objectives, you can count on those extra questions being of the beta variety. For example, a normal exam is around 60 questions and allots 1.5 hours to complete the exam, whereas a beta exam will be 80 questions and is alloted 2 hours to complete. Unfortunately, the beta questions are interspersed with the exam questions that count for your score and you can’t safely ignore or skip any question.
For those who have left-over mental capacity while taking an exam, beta or otherwise, please help the process by adding a comment to any question that seems to have a problem or that you feel could be made either more clear or to the point. You’ll get a nice warm feeling of helping others and who knows, you might want to join the exam development group as a result.
Tips and Tricks to Succeed
One of the strategies that attendees seem to have great success with is skipping and marking questions they don’t know or that will take a lot of time to answer. This requires a lot of discipline, contrary to conventional wisdom. I’ve heard of people getting the answers to previous questions from reading and answering later ones—several people who experienced mental vaporlock had their memories jogged by a question and were able to navigate back and change a wrong answer.
This isn’t cheating, no matter what a purist might say. It’s intelligent use of the interface and your own skills; the testing environment is stressful enough without having your brain lock up on you. Additional stressors include a boss who said, “Don’t come back without your certification,” and knowing that everyone else is waiting for you to emerge victorious before they take the exam! Nothing like being the point man or woman….
Ending the Exam
The next-to-last screen presented at the end of the exam is the Review screen. This is where you can see whether you’ve not answered a question (denoted by a red mark next to it), left any choose-two or three questions with too few answers (same red mark), or marked any questions for review (black check/X next to it).
Warning: It’s essential that you revisit the incomplete or marked questions before you click the End Exam button because it’s too late then!
A certain number of attendees will try to outguess the interface and leave the choose-all type of questions with a single or no answer. This does not generate a red mark next to the question, and you might well forget the question, getting it completely wrong.
Tip: If you marked questions and don’t know the answers, for heaven’s sake, guess! It’s possible you’ll get some right and I have seen examinees miss passing by one question in this situation, don’t let it be you!
The exam ends when you click the End Exam button. The system will print out two sheets; the section scores will be on the second sheet. You’re not informed of your score until you get out of the exam room or to the printer!
Getting Your Score
This I feel is unnecessarily stressful and can give your evil-minded instructor a chance to mess with you! If a candidate has actually failed an exam, we are straight-faced, empathetic and helpful in remedying their situation with study tips and the odd shoulder to sob on. However, if a cocky student does pass and needs a bit of teasing, we’re entirely capable of greeting them with a long and serioius face and a conciliatory pat on the back, then springing the winning score on them! Hilarity often ensues.
Enjoy,
RossB
Copyright 2000-2009 Ross Brunson
Question Dissection: Run Commands via LILO
Posted by RossB in Articles, Books, Question Dissection Series on 2010/04/14
Note: The Question Dissection Series is designed to present a sample LPIC Exam question taken from various sources for study, providing the right and wrong answers with explanations designed to show you how questions should be read and understood. Additionally there are Notes that point to sites, resources and other tools to help you study properly for the concepts contained in the question.
Question: Run Commands via LILO
From objective 101.2 Install a Boot Manager
Which of the following LILO command options causes the foobar command to be executed upon reboot of the machine?
❑ A. lilo –b foobar
❑ B. lilo –R foobar
❑ C. lilo –v foobar
❑ D. lilo < foobar
Answer B is correct because the R option is designed to run a command upon the next system boot. Answer A is incorrect because the b option is for specifying the boot device.
Answer C is incorrect because the v option specifies verbosity when the command is run.
Answer D is incorrect because the lilo command doesn’t accept input in this fashion.
Notes: LILO allows for command execution upon next boot, and knowing how this works can shorten the cycle of a scripted installation, new software installation or updates etc. In addition, knowing how to install, configure and troubleshoot LILO is still an important skill to possess as a sysadmin, although distributions are using GRUB more than ever these days.
Several resources can be helpful in learning more about this topic, the first of which would be Chapter 1 of the current version of my LPIC 1 Exam Cram 2 book (look for it in the sidebar ->), starting on Pg 14, the second would be the lilo man pages ( man lilo ).
Any comments, suggestions or questions are welcome.
RossB
Copyright 2000-2009 Ross Brunson
Command Post: Using the Shell *UPDATED*
Posted by RossB in Articles, Command Post Series on 2010/04/12
Command Post is a series designed increase your understanding of a given command, it’s configuration files, usage and tips for exam questions about the command.
Understanding Shells
A shell is a program designed to interpret the commands users type, parse for expansions and wildcards, and then produce instructions to the computer to accomplish those tasks.
Unless you change the defaults, the Linux shell is normally the bash shell. Of course, many other shells exist. A partial list is shown in the following table.
Among other pieces of information, the user’s default shell is specified in the /etc/passwd entry for that user. If the shell that is specified does not exist, the user is not permitted to log in.
Special shells can be specified, such as /bin/false (which returns a nonzero error code, effectively blocking access by a user attempting to log in) or /etc/nologin (which is used to block logins for accounts that have been disabled and echo a message that login is denied). The /etc/nologin file might not exist on some systems.
Deconstructing a Login Shell Session
A login shell is one that is executed when logging in to the system. The /etc/profile file is the global configuration file that affects all users’ environments if they use the bash shell. It’s sourced (read) every time a user performs a login shell. This file is a script and is executed right before the user’s profile script. The user’s ~/.bash_profile script, if it exists, is the next script that’s sourced. This file contains variables, code, and settings that directly affect that user’s—and only that user’s—environment. This script calls, or sources, the next script, which is .bashrc.
The .bash_profile script can also be referred to or named as the .bash_login or .profile script. If all three exist, the .bash_profile is sourced alone; otherwise, if it doesn’t exist, the .bash_login is sourced. Finally, if the first two are nonexistent, the .profile script is sourced. This functionality is used almost entirely by Bourne shell users upgrading to a bash system as a way to keep their settings in the same .profile file.
The .bashrc file is called by the .bash_profile or one of the profile’s aliases and is used to set various shell settings and options, set the prompt, and define aliases and functions for command-line execution. The last script sourced during a user’s login session is the .bash_logout file. This file is used to issue the clear command, so text from any previous command is not left on the user’s screen after he logs out.
TIP: Be careful on the exam because a lot of test-takers do not pick the .bash_logout file as part of the user’s login session. It’s definitely one of the more missed elements in the shell section.
An example of the user’s login session might be the following:
1. The user logs in with a username and password.
2. The /etc/profile is sourced.
3. The user’s .bash_profile is sourced.
4. The user’s .bashrc is sourced from within the .bash_profile.
5. The user conducts his business.
6. The user initiates a logout with the logout or exit command or by
pressing Ctrl+D.
7. The user’s .bash_logout script is sourced.
Summary
Remember these important things: 1. Executing a script file only loads the settings contained in it within the life of the sub-shell the script executes in, they are gone when the sub-shell exits. 2. Sourcing a script file ( preceeding it with dot, such as ” . /etc/bashrc” will load the variables and settings in that file into the current shell.
For more information on how to use the shell, you can turn to many multiple resources, including Chapter 2 of the current version of my LPIC 1 Exam Cram 2 book (look for it in the sidebar ->), starting on Pg 28, the second would be the bash shell’s man page (man bash), still another would be the Guides section of The Linux Document Project’s site, particularly the Bash Guide for Beginners.
Any comments, suggestions or questions are welcome.
RossB
Copyright 2000-2009 Ross Brunson
Certifiable: Preparing for the LPIC Level 1 Certification – Part 3
Posted by RossB in Articles, Certifiable Series on 2010/04/07
Certifiable is a series dedicated to helping you get ready to take the LPIC 1 exams, both in mental state and how to study and experiment more effectively.
Registering and Taking LPI Exams
There are three things you need to do to take an LPI exam with one of the testing providers:
- Get Your Candidate ID from LPI
- Register and Schedule Your Exam
- Show up and take the Exam
Getting Your Candidate ID from LPI
The first thing you’ll have to do as an LPI exam candidate is to go to the LPI site and register to get your candidate ID. You can do this by navigating to the LPI home page, then select the “Certification” button on the top menu to open the Certification page, and click on the “Register Now” link on the left panel. This will take you to the Registration page, where you can click on the “register here” link to start the registration process.
Note: If you already have an LPI Candidate ID, you should NOT register yourself again, you’ll have multiple ID’s and exams won’t count properly.
Completing the registration is a three step process:
- Register for an LPI ID.
- Set up preferences.
- Optional demographic information.
Once you’ve filled out the form and agreed to the terms, press the “Submit” button and you’ll be shown a page that contains your sparkling-new LPI ID. Print the page, email it to yourself, write it down, but remember that number, it’s key to being able to schedule an exam with the testing providers.
Note: If you somehow lose the number, or the browser crashes before you can print it out or write it down, just login to the LPI member area and you’ll see your number at the top of the page.
Registering and Scheduling an Exam
Taking your exam requires you to register and pay for the exam first, which you can do by visiting either VUE or Prometric‘s sites. For example, to register and schedule an exam via VUE, you would navigate to the VUE website, click on the “Learn” tab and from the menu in the middle of the page select “Information Technology – IT” and scroll down in the right panel to select the “Linux Professional Institute — LPI” item.
This will load up the page that pertains to the LPI Programs, where you can search for the right exam, locate a testing center, manage your exams and get support for any issues you might encounter. You can also navigate directly to this page by appending “/lpi” to the end of the VUE site URL.
There are three options for scheduling an exam:
- Schedule Online
- Schedule by Phone
- Schedule through Testing Center
Warning: if you choose to schedule online you will have to go through yet ANOTHER registration process with the testing provider to complete the scheduling online.
Show Up and Take the Exam
When you arrive at the testing center to take your exam, you need to sign in with an exam proctor. They will ask you to show two forms of identification, one of which must be a photo ID, preferably government issued. After you have signed in, you are asked to deposit any books, bags, or other items you brought with you. Then you are escorted into the closed room that houses the exam seats.
All exams are completely closed book, open mind. In fact, you typically aren’t permitted to take anything with you into the testing area. Some centers are a little more relaxed than others; shop around to find one that suits you. Some gladly give you extra paper or laminated sheets, but others might seem stingy or suspicious of your motives. Try to understand what might have caused those behaviors—for instance, the center might have been plagued by cheaters and questionable examinees in the past.
You will be furnished with a variety of possible note-taking materials, all of which must be surrendered upon exiting the exam room. Possible scenarios include: a pen or pencil and blank sheets of paper; a notepad of paper and writing implements; and a laminated sheet of paper and an erasable felt-tip pen.
Tips for Remembering Key Information
You are allowed to write down any information you want on your writing tablet or whatever the center has provided for you. You should memorize as much of the material you think you’ll have a hard time with, charts, tables etc. so you can write that information on the blank sheets as soon as you are seated in front of the computer. Take a few minutes before you hit the exam start button to write down all the items you memorized and think you’ll need.
Tip: Here’s the key to using the writing materials you have been given: Write down anything you want to remember for the exam, starting from the moment they sign you in.
They (the mythical they) say that humans only use 10% of their brain’s capacity, with no one quite sure what the other 90% is taken up with. I can tell you something that no scientist will agree with, but I know to be true for techies: It’s all operating system overhead! We use it for motor skills, surfing games, and finding the nearest Starbucks.
You have only a limited amount of mental RAM, so use it wisely and commit things you know you’ll need to paper as a way to free up that 10% of your brain so it can all be used for the purpose of taking the exam.
The Testing Room
Typically, the room will be furnished with anywhere from 2 to 30 computer stations, each of which should be separated from the others by dividers designed to keep you from seeing what is happening on someone else’s computer. Most test rooms feature a wall with a large picture window. This permits the exam proctor to monitor the room, prevent exam takers from talking to one another, and observe anything out of the ordinary that might go on. The exam proctor will have preloaded the appropriate LPIC certification exams. You’re permitted to start as soon as you sit down in front of the computer. Ensure that you agree to the testing agreement, as refusing to do so will void your exam.
Note; You might experience a wide variety of types and styles of testing centers, as well as differences in enforcement of policy, so shop around and find one that meets your needs and style. I have literally taken exams in an approved testing center that was off to the side of an airplane hangar, with a friendly but somewhat-disinterested cat sitting on the table while I took my exam.
Enjoy,
RossB
Question Dissection: Kernel Modules Loaded
Posted by RossB in Books, Question Dissection Series on 2010/04/03
Note: The Question Dissection Series is designed to present a sample LPIC Exam question taken from various sources for study, providing the right and wrong answers with explanations designed to show you how questions should be read and understood. Additionally there are Notes that point to sites, resources and other tools to help you study properly for the concepts contained in the question.
Question: Kernel Modules Loaded
From objective 101.1 Determine and configure hardware settings
Which command shows currently loaded Kernel modules and their dependencies? (Choose all that apply.)
❑ A. cat /proc/modules
❑ B. lsdev
❑ C. cat /proc/kernel/modules
❑ D. lsmod
❑ E. kmod –list
Answers A and D are correct because they display nearly identical
information about the loaded modules and their dependencies.
Answer B shows the system’s devices, I/O ports, DMA, and IRQs but not modules, so it’s incorrect.
Answer C is incorrect because that directory and file path do not exist.
Answer E is incorrect because there is no such option for the kmod daemon.
Notes: Traditionally, a Linux installation has included a little to a lot of troubleshooting, and the ability to determine what Kernel modules are loaded is key to fixing issues with hardware. One of my favorite ways to troubleshoot these sorts of situations is after the installation fails, or you can’t configure X or a DVD-ROM drive, boot up a Live CD from openSUSE or Knoppix and then run the various module-related commands to gather information on what works. Then it’s a matter of using that information to get the appropriate driver modules loaded on the troubled installation. Another trick is to find a similar machine that is currently working, and use the module-related commands to do the same thing as mentioned above.
Several resources can be helpful in learning more about this topic, the first of which would be Chapter 1 of the current version of my LPIC 1 Exam Cram 2 book (look for it in the sidebar ->), starting on Pg 6, the second would be the lsmod man pages ( man lsmod ).
Any comments, suggestions or questions are welcome.
RossB
Copyright 2000-2009 Ross Brunson