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

What is a RAID?


Redundant Array of Independent Disks (RAID) is often either a software- or hardware-based system that allows users to take multiple disks and use them as one device. The RAID can be configured in multiple ways, allowing for either greater data redundancy or performance.

This configuration is commonly referred to as a RAID level. The different types of RAID levels provide different functionality to get a better idea of the RAID levels. Let's explore a few that are commonly used.

RAID 0 – striping

RAID 0 is one of the simplest RAID levels to understand. The way RAID 0 works is by taking multiple disks and combining them to act as one. When data is written to the RAID device, the data is split and parts are written on each disk. To understand this better, let's put together a simple scenario.

  • If we had a simple RAID 0 device that consisted of five 500 GB drives, our RAID device would be the size of all the five drives together—2500 GB or 2.5 TB. If we were to write a 50 MB file...