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

Establishing a hypothesis

At this stage of the troubleshooting process, we will take all of the information that we have gathered and use it to establish an idea as to why the issue occurred and what can be done to resolve it.

To start, let's first review what we have learnt from the Data Gathering steps.

  • An established blog site is currently showing a page that is designed to only be shown during initial installation of the blog software

  • The blog is using the open source software WordPress

  • WordPress is written in PHP and utilizes both Apache and MariaDB services

  • Apache and PHP are working correctly and showing no errors

  • The WordPress installation is located at /var/www/html

  • The MariaDB service is up and accepting connections

  • The WordPress application is able to connect to the database service

  • When reading from the database tables, we receive an error that indicates an issue with the files that contain the database data

The hypothesis that we can formulate from all of these data points is as follows...