11/7/2001 -- It seems as though CompTIA is rapidly moving into a position where they offer an exam and certification for everyone. Their most-recent exam is Linux+, which is aimed at the entry-level Linux administrator. The exam costs $190 ($140 for CompTIA members), features 95 questions, and is available through Prometric and Vue testing centers.

The Facts
The Linux+ exam is comprised of seven major objective categories, called "domains." A weighting is assigned to each category to determine how many questions will come from that category. The categories and weighting employed are as follows:

• Planning the Implementation – 4%
• Installation – 12%
• Configuration – 15%
• Administration – 18%
• System Maintenance – 14%
• Troubleshooting – 18%
• Identify, Install, and Maintain System Hardware – 19%

Although there are no prerequisites for this certification, the last domain should clue you to the fact that A+ (hardware) certification is strongly recommended. In addition to the 19% of the exam specifically listed as covering hardware as a top-level domain, hardware topics also appear within objectives throughout the other domains. Indeed, a solid understanding of hardware is essential for approximately 35-40% of the exam. (For a more detailed list of the objectives, click here.)

All questions are either multiple-choice with at least four possible choices or "point-and-click" graphic questions. Of the multiple-choice questions, there are a mixture of "choose one" and "choose more than one" questions. The grading scale is between 100 and 900, with a passing score being above 655.

The Inside Scoop
The components of the Linux+ exam can be classified in one of three ways: good, bad, and so-so. On the good side, it is the only Linux certification that requires only one exam. CompTIA has proven time and time again that there is a need for verification of a person’s skills with a single exam, and this is another excellent opportunity put to good use. I've run in to dozens of people proclaiming that they know Linux -- really know Linux. What that really translates into, though, is different for everyone. Whereas one person interprets "knowing Linux" as being able to recompile the kernel on-the-fly, another thinks it merely means knowing the difference between the grep and diff utilities. Linux+ certifies that a person knows the basics of the operating system on a level platform and can operate as an entry-level administrator.

Now to the bad side. Because of its advertised experience level (six months), you can easily be lulled into a false sense of confidence with this exam. Try and pass the exam without studying and you'll likely leave the test center $190 poorer and with a severe blow to your pride. The six-months-experience target audience this exam is more for is one who eats and sleeps in the server room; who clips the pager around the neck of their T-shirt because the cell phone and other devices are occupying all the available belt room. You need to study for this exam as you would any other.

The so-so portion of the exam is more a personal preference of mine than anything else. Instead of the exam asking 95 questions, I’d prefer to see fewer questions, and have those questions left employ more difficult technology. Everyone knows that Linux is a case-sensitive operating system and so much of its power lies at the command line. It seems a waste to not have fill-in-the-blank questions testing comprehension of common commands (change the password to …, kill a process, etc.) When you get to 95 multiple-choice questions, you border on questions that have to be in a simplistic, multiple-choice format in order for candidates to be able to answer all of them in the time allotted.

How To Study
Linux is an operating system that grew out of open cooperation between users and developers around the world. Profit was never a motive in the development of the operating system, and it has remained that way throughout its history. Today, you can still find all the resources needed to assist with any problem online and freely distributed. This holds true for exam preparation as well.
The following is my recommendation for how to study for, and pass, this exam with the fewest steps and the smallest cost possible:

1. Print the complete list of the domain objectives and subobjectives. These can be found at http://www.comptia.org/certification/linuxplus/linuxplus_blueprint.pdf.

2. Carefully examine the list of objectives and find out what knowledge is expected beneath each. 8Wire.com ran a seven-part series dissecting each of the objectives for the exam. The first article in the series can be found at http://www.8wire.com/articles/?AID=2374. You can find links from there to the other articles in the series.

3. Check off the objectives that you know from having worked hands-on with Linux, and make a note only of the topic areas that you are most unfamiliar with. Research the topics on the list by first going to http://www.unixreview.com/documents/s=1442/urm0110c/0110c.htm and finding the links given there for that objective.

4. After researching the topics, work with the associated commands or utilities on a test system. For example, if you start out not knowing much about printers and their configuration, first research the topic, then edit the /etc/printcap file on a test system, and work with the related utilities. While Linux is a "vendor-neutral" topic by nature, the authors of the Linux+ exam questions tend to favor Red Hat. I would strongly encourage you to run their version of the operating system on your test machine.

5. Take at least one sample test (preferably more) to verify your knowledge. You can find sample tests on Linux from a number of vendors. Coriolis, for example, offers a Question of the Day on General Linux that you can subscribe to at www.examcram.com. If you are able to get 90% or more of the sample test correct, you are ready to register for the real thing. If you cannot score well on the sample test after following this path, then you will need to invest a few dollars and turn to self-study resources, such as training guides or study guides. As of this writing, the only one currently available is the Linux+ Study Guide by Roderick Smith (Sybex, ISBN: 0782129390). Five other titles are scheduled to appear shortly.

Alternatives
In addition to CompTIA’s certification offering, there are two other vendor-neutral certifications in Linux currently available: Linux Professional Institute(LPI) and Sair. To become LPI certified at the first level – the only one currently available – you must pass a series of two exams. With Sair, to become certified as a Linux Certified Administrator (LCA), you must pass four exams (passing Installation and Configuration 101 by itself will earn you the designation of Linux Certified Professional, however). Information on LPI certification can be found at http://www.lpi.org. Information on Sair certification can be found at http://www.linuxcertified.com.

Sample Questions
The following sample questions will help to test your knowledge of basic Linux topics. They are excerpted from the LPI General Linux I Exam Cram: Exam 101 (Coriolis; ISBN: 1576109232). Although written for LPI, there is enough overlap in objectives that they are also useful for Linux+ study.

1. Martin calls you on the telephone. He has a file named "marketinfo" that has 56,000 lines in it, and he wants to see only the last 10,000. Which of the following commands should you tell him to run?

A. tail +46000 marketinfo
B. tail +10000 marketinfo
C. tail -46000 marketinfo
D. head +46000 marketinfo
E. head -10000 marketinfo
F. tail +46001 marketinfo

2. At the command line, Tim has given the command TODAY=Friday. Which of the following will show that the variable TODAY is equal to a value of Friday?

A. set
B. env
C. show
D. display

3. Which of the following commands will send the errors from the abc application to a file, but not the standard output?

A. abc > abc.error
B. ABC 2 > abc.error 2>&1
C. ABC 2> abc.error
D. ABC>> abc.error

4. Tim has a large file that exceeds the size of a floppy's storage capacity. He wants to put the file on two floppies so he can take it with him when he joins the competition. What command can he use to make the file fit two floppies?

A. nl
B. cut
C. fmt
D. split

5. You wish to combine two files together such that the fields from each file are combined into a single output file. The first field of each of the two starting files is identical--equal to the employee number. Which utility should you use to create the output file?

A. join
B. paste
C. cat
D. od
E. sort

Answers
1. F. To see only 10,000 lines out of 56,000, Martin must start with number 46,001 and view the remaining lines. Answer a would show 10,001 lines at the end of the file, whereas answer b would start with 10,000 and end up displaying 46,001 lines. Answer c would display the last 46,000 lines, and answer d is invalid because head does not have a + option. Answer e would display the first 10,000 lines and not the last.

2. A. Until the variable is exported, it will not show up in the environment (answer b) but will display with the set command. Answers c and d are invalid options for this question (they don't exist).

3. C. This will send the errors to the file, but not the standard output. Answer a will send standard output to the file, but not the errors. Answer b will send both errors and standard output to the file. Answer d will append standard output to the file, but not redirect errors.

4. D. The split command will chop the file into smaller entities. The nl command (answer a) simply numbers the lines of output. The cut command (answer b) will remove fields of output, but it won't change the size of the file. The fmt command (answer c) can format display-per-line size and other variables but does nothing for reducing a file's size.

5. A. When the files share something in common (the first field in this case), the join utility can combine them together. If they share absolutely nothing in common, then paste (answer b) can be used. The other commands will not combine files together in the way specified.