Chapter 2. Troubleshooting Commands and Sources of Useful Information

In the first chapter, we covered troubleshooting best practices and the high level process involved. Where the first chapter was a 20,000 ft view on troubleshooting, this chapter starts to dive into the specifics.

This chapter will review common troubleshooting commands as well as common places to find helpful information. Within this book, we will utilize release 7 of Red Hat Enterprise Linux (also referred to as RHEL). All commands referenced in this chapter will be commands that are included with a default installation of RHEL 7.

We will reference commands that are installed by default, as I have found myself in situations where I could have used a specific command to identify an issue immediately but that command was not available to me. By limiting this chapter to default commands, you can be assured that the troubleshooting steps covered in this chapter are not only relevant to most RHEL 7 installations, but are also relevant to previous releases and other Linux distributions.