Mark Sobell, author and president of consulting firm Sobell Associates Inc., has released a second edition of his book, A Practical Guide to Ubuntu Linux. This new edition, focusing on Ubuntu versions 8.10 and 8.04, provides a step-by-step approach for beginners as well as professionals for understanding and using an Ubuntu Linux system. We asked Sobell several questions concerning the contents, procedures and tools outlined in his 28-chapter depiction of Ubuntu Linux, from installing the system to setting up secure servers that run on the system, to give readers some insight into what the book is all about. The publisher has provided SearchEnterpriseLinux.com with a free download of Chapter 11 of A Practical Guide to Ubuntu Linux, second edition, "System Administration: Core Concepts."
We asked Sorbell a few questions about the book, and how he makes Ubuntu more understandable to those who may be intimidated.
Many feel Ubuntu Linux is an intimidating topic. Is that your experience, and how did that influence your decision to write this book?
Mark Sobell: Installing and using Linux used to be much more difficult than it is today, and therefore more intimidating, especially to someone who was not computer savvy. Linux distributions, particularly Ubuntu, have done a lot to make Linux less intimidating. Installation, even of a dual-boot system is now quite easy. If you accept the default values, installation is typically a matter of pressing RETURN a few times.
Another example of how Ubuntu has made Linux easier to use is what happens when you try to play an MP3 music file: you click an icon for an MP3 file and the operating system asks if you want to install the software necessary to play the music. Click YES, Ubuntu installs the software, and you are set to go. Other releases simply inform you that the system is not set up to play MP3 files because MP3 is not a free format.
I wrote my first Linux book in 1997, when Linux was a lot less user friendly. My objective then was the same as it is today: making Linux more accessible to more people.
What do you think is the most commonly misunderstood topic or procedure concerning Ubuntu Linux? How did you address this in your book?
Mark Sobell: I am not sure there is one common problem area. One person may be confused by partitioning a disk during installation while another might have a problem setting up a DNS server. In the sections of the book where I describe a process that uses a GUI, I use screen shots alongside the description to make the explanations more clear. In the case of command line procedures, I provide line-by-line examples that show the reader what he/she will see on the screen when following the instructions.
What are the major differences between the second edition of your Ubuntu book and the first edition?
Mark Sobell: The second edition covers Ubuntu 8.04 LTS (Hardy Heron, maintained until 2011) and Ubuntu 8.10 (Intrepid Ibex). I point out and explain differences between the two versions. The first edition covered Ubuntu 7.10 (Gutsy Gibbon).
Aside from the releases that the books cover, the biggest difference is the addition of a chapter on the Perl scripting language. Because Ubuntu uses Perl for many administration scripts I thought readers who want to dig a little deeper into Linux would appreciate an introduction to this language. In addition there are new sections on LDAP and ufw (uncomplicated firewall).
One reviewer said your book bridges the gap between Linux, Windows, and UNIX. Was this part of your plan in writing the book, and why did you think that was important?
Mark Sobell: Well, the gap between Linux and UNIX is not that great for many users. My book will help someone transition from UNIX to Linux, but several chapters (such as the filesystem and first shell chapters) will be redundant for those readers. Probably the most helpful chapters for a UNIX user will be the installation, system administration, and server chapters (Parts I, IV, and V). And of course the new Perl chapter in Part VI.
The chapters that someone who is familiar with UNIX skips will be the ones that help a Windows user get started with Ubuntu. After reading Part I to install Ubuntu, Part II introduces the GUI (GNOME), command-line utilities, the Linux filesystem, and the Bourne Again Shell (bash). Part III goes into more detail about GNOME, the X Window System, bash, and networking. After reading those chapters a Windows user will be up to speed with Linux and can continue with Parts IV and V.
Who is the intended reader of your book? Who did you have in mind while writing the book?
Mark Sobell: I designed the Ubuntu book to appeal to readers at several levels. A reader who is new to Linux can read the book from beginning to end to get a good foundation in many topics including installation, using Ubuntu from a GUI and from the command line, system administration, server setup, as well as shell and Perl programming. An experienced user might want to read a chapter here and there, using the book more as a reference. I have gotten many comments that my books are good references-- people keep them on their shelves and refer to them as needed.
Some critics say you went into very thorough detail concerning certain issues, while you did not go into specifics about other topics. Can you explain your reasoning regarding leaving out details for some topics while concentrating on others?
Mark Sobell: I am not sure which sections these critics are referring to so it is hard to answer this question. The book is about 1200 pages and is intended to introduce readers to many topics. Most chapters have a "More Information" section that cites resources for readers who want to learn more than is covered in the chapter.
Take Chapter 20 as an example. This chapter covers setting up an exim4 mail server in two configurations and explains many options. It also covers setting up SpamAssassin, Webmail (SquirrelMail), mailing lists (Mailman), IMAP and POP3 mail servers, and how to set up authenticated relaying using SSL. That information could occupy a whole book. I provide enough information so a reader can set up and use these tools. My objective is to introduce a wide variety of tools and bring the reader to a level of competence from which she/he can use each tool and know what questions to ask and where to look for more information.
Chapter 11 goes into great detail concerning the use of sudo and su. Can you give examples of situations when one tool is better than the other?
Mark Sobell: Using sudo in place of su can make a system more secure. One of the main benefits of sudo is that it enables an administrator to allow certain users to run specific programs as a privileged user (root) while not giving those users unrestricted root privileges.
I have not found anything that I can do with su that I cannot do with sudo. On a system with one user, where that user is also the system administrator, using sudo has few advantages over su. If a user on one of these systems is more comfortable using su, there is minimal security loss caused by unlocking the root account and using su to gain root privileges. When you work on systems with several users and with networks of systems, sudo has many advantages. On these systems it is poor practice to unlock root.
This excerpt offered here is from the new 2nd Ed. of A Practical Guide to Ubuntu Linux, authored by Mark Sobell, published by Prentice Hall Professional, Copyright 2009, Mark G. Sobell. For more information on this book, please visit: A Practical Guide to Ubuntu Linux's product page and for more sample content, click here. To learn more about Mark Sobell's books, please visit: www.sobell.com.
ABOUT THE AUTHOR: Erin Kelly is an editorial assistant at TechTarget. Erin is a Northeastern coop student who will be working at the company until the end of June. She supports the Data Center and Virtualization and Storage media groups through a variety of editorial duties. Erin studies journalism and writes for the Huntington News, an independent print and online paper produced by Northeastern students. You can contact her at firstname.lastname@example.org.