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
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

A reported issue


Much like the previous chapter, which focused on an issue with a custom application, today's issue comes from the same custom application.

Today, we will be working on an issue reported by an application support team. However, this time the support team was able to provide us with quite a bit of information.

The application we were working on in Chapter 9, Using System Tools to Troubleshoot Applications, now receives messages over port 25 and stores them in a queue directory. Periodically, a job runs to process those queued messages, but the job doesn't seem to be working anymore.

The application support team has noticed quite a large amount of messages backlogged in the queue. However, even though they have been troubleshooting the issue as much as possible, they are stuck and require our assistance.