the skills needed to compete for the thousands of well-paying Linux administrator or development jobs, it will help you to know how to install, secure, and maintain Linux systems.
In March 2020, more than 60,000 jobs requiring Linux skills were listed at Indeed.com. Nearly half of those offered pay of $100,000 per year or more. Site such as Fossjobs.net provide a venue for posting and finding jobs associated with Linux and other free and open source software skills.
The message to take from these job sites is that Linux continues to grow and create demands for Linux expertise. Companies that have begun using Linux have continued to move forward with it. Those using Linux continue to expand its use and find that cost savings, security, and the flexibility it offers continue to make Linux a good investment.
Understanding how companies make money with Linux
Open source enthusiasts believe that better software can result from an open source software development model than from proprietary development models. So, in theory, any company creating software for its own use can save money by adding its software contributions to those of others to gain a much better end product for themselves.
Companies that want to make money by selling software need to be more creative than they were in the old days. Although you can sell the software you create, which includes GPL software, you must pass the source code of that software forward. Of course, others can then recompile that product, basically using and even reselling your product without charge. Here are a few ways that companies are dealing with that issue:
Software subscriptions: Red Hat, Inc., sells its Red Hat Enterprise Linux products on a subscription basis. For a certain amount of money per year, you get binary code to run Linux (so you don't have to compile it yourself), guaranteed support, tools for tracking the hardware and software on your computer, access to the company's knowledge base, and other assets.Although Red Hat's Fedora project includes much of the same software and is also available in binary form, there are no guarantees associated with the software or future updates of that software. A small office or personal user might take a risk on using Fedora (which is itself an excellent operating system), but a big company that's running mission-critical applications will probably put down a few dollars for RHEL.
Training and certification: With Linux system use growing in government and big business, professionals are needed to support those systems. Red Hat offers training courses and certification exams to help system administrators become proficient using Red Hat Enterprise Linux systems. In particular, the Red Hat Certified Engineer (RHCE) and Red Hat Certified System Administrator (RHCSA) certifications have become popular (https://www.redhat.com/en/services/training-and-certification/why-get-certified). More on RHCE/RHCSA certifications later in this chapter.
Other certification programs are offered by Linux Professional Institute (https://www.lpi.org) and CompTIA (wwww..comptia.org/). LPI and CompTIA are professional computer industry associations.
Bounties: Software bounties are a fascinating way for open source software companies to make money. Suppose that you are using XYZ software package and you need a new feature right away. By paying a software bounty to the project itself, or to other software developers, you can have your required improvements moved to the head of the queue. The software you pay for will remain covered by its open source license, but you will have the features you need—probably at a fraction of the cost of building the project from scratch.
Donations: Many open source projects accept donations from individuals or open source companies that use code from their projects. Amazingly, many open source projects support one or two developers and run exclusively on donations.
Boxed sets, mugs, and T-shirts: Some open source projects have online stores where you can buy boxed sets (some people still like physical DVDs and hard copies of documentation) and a variety of mugs, T-shirts, mouse pads, and other items. If you really love a project, for goodness sake, buy a T-shirt!
This is in no way an exhaustive list, because more creative ways are being invented every day to support those who create open source software. Remember that many people have become contributors to and maintainers of open source software because they needed or wanted the software themselves. The contributions they make for free are worth the return they get from others who do the same.
Becoming Red Hat certified
Although this book is not focused on becoming certified in Linux, it touches on the activities that you need to be able to master to pass popular Linux certification exams. In particular, most of what is covered in the Red Hat Certified Engineer (RHCE) and Red Hat Certified System Administrator (RHCSA) exams for Red Hat Enterprise Linux 8 is described in this book.
If you are looking for a job as a Linux IT professional, RHCSA or RHCE certification is often listed as a requirement, or at least a preference, for employment. The RHCSA exam (EX200) provides basic certification, covering such topics as configuring disks and filesystems, adding users, setting up a simple web and FTP server, and adding swap space. The RHCE exam (EX300) tests for more advanced server configuration as well an advanced knowledge of security features, such as SELinux and firewalls.
Those of us who have taught RHCE/RHCSA courses and given exams (as I did for three years) are not allowed to tell you exactly what is on the exam. However, Red Hat gives an overview of how the exams work as well as a list of topics that you can expect to see covered in the exam. You can find those exam objectives on the following sites:
RHCSA
https://redhat.com/en/services/training/ex200-red-hat-certified-system-administrator-rhcsa-exam
RHCE
As the exam objectives state, the RHCSA and RHCE exams are performance based, which means that you are given tasks to do and you must perform those tasks on an actual Red Hat Enterprise Linux system, as you would on the job. You are graded on how well you obtained the results of those tasks.
If you plan to take the exams, check back to the exam objectives pages often because they change from time to time. Also keep in mind that the RHCSA is a standalone certification; however, you must pass the RHCSA and the RHCE exams to get an RHCE certification. Often, the two exams are given on the same day.
You can sign up for RHCSA and RHCE training and exams at https://redhat.com/en/services/training-and-certification. Training and exams are given at major cities all over the United States and around the world. The skills that you need to complete these exams are described in the following sections.
RHCSA topics
As noted earlier, RHCSA exam topics cover basic system administration skills. These are the current topics listed for Red Hat Enterprise Linux 8 at
