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

Chapter 5. Network Troubleshooting

In Chapter 3, Troubleshooting a Web Application, we took an in-depth look at troubleshooting web applications; while we walked through a complex application error, we completely skipped the networking aspect of web applications. In this chapter, we will investigate a reported issue that will walk us through concepts such as DNS, routing, and of course network configuration for RHEL systems.

Networking is an essential skill for any Linux systems administrator. To quote a past instructor:

A server without a network is useless to everyone.

As a systems administrator, every server or desktop that you manage will have some sort of network connection. Whether this network connection is within a segregated corporate network or directly connected to the Internet, a network is involved.

Since networking is such a critical topic, this chapter will cover many aspects of networking and network connectivity; however, it will not cover firewalls. Firewall troubleshooting...