Book Image

Red Hat Enterprise Linux Troubleshooting Guide

By : Benjamin Cane
Book Image

Red Hat Enterprise Linux Troubleshooting Guide

By: Benjamin Cane

Overview of this book

Red Hat Enterprise Linux is an operating system that allows you to modernize your infrastructure, boost efficiency through virtualization, and finally prepare your data center for an open, hybrid cloud IT architecture. It provides the stability to take on today's challenges and the flexibility to adapt to tomorrow's demands. In this book, you begin with simple troubleshooting best practices and get an overview of the Linux commands used for troubleshooting. The book will cover the troubleshooting methods for web applications and services such as Apache and MySQL. Then, you will learn to identify system performance bottlenecks and troubleshoot network issues; all while learning about vital troubleshooting steps such as understanding the problem statement, establishing a hypothesis, and understanding trial, error, and documentation. Next, the book will show you how to capture and analyze network traffic, use advanced system troubleshooting tools such as strace, tcpdump & dmesg, and discover common issues with system defaults. Finally, the book will take you through a detailed root cause analysis of an unexpected reboot where you will learn to recover a downed system.
Table of Contents (19 chapters)
Red Hat Enterprise Linux Troubleshooting Guide
About the Author
About the Reviewers

Data collection

According to the troubleshooting process that we have been following, the next step is to gather as much data as possible around the issue. One of the best sources of information is the person reporting the issue; for this situation, we will ask two basic questions:

  • How can I duplicate the issue and see the error?

  • Has anything changed recently with the WordPress application?

When asked, the developer states that we can see the error simply by going to the blog in the web browser. On the second question, the developer informs us that the database service was recently moved from the webserver to a new dedicated database server. He also mentions that the move happened several days ago and that the application was working until today.

Since the database service was moved several days ago and the application was working up until this morning, it is not likely that this change caused the issue. However, we should not discount this as a possibility.

Duplicating the issue

As discussed...