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

Performance issues

For this chapter, we will continue the scenario that we covered in Chapter 3, Troubleshooting a Web Application, where we are a new systems administrator at a new company. As we arrive to start our day, a fellow systems administrator asks us to look into a server being "slow."

When asked for details, the only information our colleague could provide was the hostname and the IP of the server deemed "slow." Our peer mentioned that a user reported it and that the user did not provide many details.

In this scenario, unlike in the scenario discussed in Chapter 3, Troubleshooting a Web Application we don't have much information to begin with. It also seems that we are not able to ask the user troubleshooting questions. It is not uncommon as a systems administrator to be required to troubleshoot an issue with very little information. In fact, this type of scenario is quite common.

It's slow

"It's slow" is problematic to troubleshoot. The biggest problem with a complaint about a server...