Troubleshooting CentOS


Book Description

CentOS is the enterprise-grade Linux operating system built using the same source code as Red Hat Enterprise Linux (RHEL) to provide a free-to-use alternative to Red Hat's commercial Linux offering. The purpose of this book is to build on your understanding of CentOS and to explore those mission-critical services you are entrusted to manage and maintain. Starting with a brief introduction to the overall subject of troubleshooting a CentOS server, this book will take you on a journey across the whole spectrum of issue-based problem solving, which includes active processes, the networking environment, package management, users, folders, files, shared resources, security, databases, and web-based services. By the end of the book, you will have expert-level competency in identifying and diagnosing the root causes of CentOS storage, network, and administration issues and resolving them.




Mastering CentOS 7 Linux Server


Book Description

Configure, manage, and secure a CentOS 7 Linux server to serve a variety of services provided in a sustainable computer's infrastructure. About This Book Learn how to efficiently set up and manage a Linux server using one of the best suited technologies for this purpose, CentOS 7 Personalize your Linux server and familiarize yourself with the latest tools and utilities setup provided by the new CentOS distribution Follow a step-by-step tutorial through the configuration of the requested services with the capacity to personalize them as per your needs Who This Book Is For If you are a Linux system administrator with an intermediate administration level, this is your opportunity to master the brand new distribution of CentOS. If you wish to possess a fully sustainable Linux server, with all its new tools and tweaks, that serves a variety of services to your users and customers, this book is ideal for you. It is your ticket to easily adapt to all the changes made in the latest shift. What You Will Learn Manage CentOS 7 users, groups, and root access privileges Enhance the server's security through its firewall and prevent the most common attacks from penetrating or disabling the server Explore and implement the common, useful services that a CentOS 7 server can provide Monitor your server infrastructure for system or hardware issues Create and configure a virtual machine using virtualization technologies Implement a cloud computing solution on a single node system Get an introduction to the configuration management tools and their usage Discover the importance of the tools that provide remote connection, server service security, and system and process monitoring tools In Detail Most server infrastructures are equipped with at least one Linux server that provides many essential services, both for a user's demands and for the infrastructure itself. Setting up a sustainable Linux server is one of the most demanding tasks for a system administrator to perform. However, learning multiple, new technologies to meet all of their needs is time-consuming. CentOS 7 is the brand new version of the CentOS Linux system under the RPM (Red Hat) family. It is one of the most widely-used operating systems, being the choice of many organizations across the world. With the help of this book, you will explore the best practices and administration tools of CentOS 7 Linux server along with implementing some of the most common Linux services. We start by explaining the initial steps you need to carry out after installing CentOS 7 by briefly explaining the concepts related to users, groups, and right management, along with some basic system security measures. Next, you will be introduced to the most commonly used services and shown in detail how to implement and deploy them so they can be used by internal or external users. Soon enough, you will be shown how to monitor the server. We will then move on to master the virtualization and cloud computing techniques. Finally, the book wraps up by explaining configuration management and some security tweaks. All these topics and more are covered in this comprehensive guide, which briefly demonstrates the latest changes to all of the services and tools with the recent shift from CentOS 6 to CentOS 7. Style and approach This is a detailed and in-depth guide to help you administrate CentOS 7 for the usage of your server's infrastructure and also for personal network security. Each section shows a list of tools and utilities that are useful to perform the required task, in an easy to understand manner.




CentOS Bible


Book Description

Authoritative guide to a rapidly growing Linux distribution This is one of the first, if not the first comprehensive guide to the CentOS Linux operating system. Linux guru Tim Bornocyzyk, thoroughly covers the topic whether you're a Linux novice or a regular who now wants to master this increasingly popular distribution. First find out how to install and configure CentOS. From there, you'll cover a wealth of Linux and CentOS tools, functions, and techniques, including: how to work in the GNOME and KDE desktop environments; how to use the Linux shell, file system, and text editor; how to configure CUPS printers, Samba for file and printer sharing and other features using GUI tools; and more. CentOS (Community ENTerprise Operating System) is a Linux operating system maintained by a small team of core developers based on Red Hat Enterprise Linux (RHEL) Lead author Christopher Negus is the bestselling Linux author of such books as Fedora 10 and Red Hat Enterprise Linux Bible and Linux 2009 Edition Bible; he is also a member of the Red Hat Enterprise Linux training team Tech edited by key member of the CentOS development team, Ralph Angenendt, and foreword written by lead CentOS developer, Karanbir Singh. Learn how to set up users, automate system tasks, back up and restore files, and prepare for the latest security issues and threats; also learn how to use and customize the desktop menus, icons, window manager, and xterm; and how to create and publish formatted documents Explores available Linux multimedia applications for graphics, audio, video and CD burning The DVD includes complete copy of the most current CentOS Distribution – CentOS 5.3 For getting the most out of CentOS Linux, this is the book you need to succeed. Note: CD-ROM/DVD and other supplementary materials are not included as part of eBook file.




CentOS 7 Linux Server Cookbook


Book Description

Over 80 recipes to get up and running with CentOS 7 Linux server About This Book A practical guide to install, configure, administer and maintain CentOS 7 servers An in-depth guide to the CentOS 7 operating system, exploring its various new features and changes in server administration Presents tricks and solutions to tackle common server issues with the help of practical examples and real-life scenarios Who This Book Is For This book is targeted at beginner and more experienced system administrators alike who want to use CentOS as their server solution. Readers do not need much pre-knowledge or experience at all to work with this book. What You Will Learn Install and configure CentOS 7 Linux server system from scratch using normal and advanced methods Maintain a performance-based and secure server solution by deploying expert configuration advice and managing software packages Monitor, manage and develop your server's file system to maintain a stable performance Gain best practice methods on sharing files and resources through a network Install and configure common standard services such as web, mail, FTP, database and domain name server technologies Introduce you to the world of operating-system-level virtualization using the Docker platform. Understand the fundamentals of the Security-Enhanced Linux access control architecture Monitor your IT infrastructure using Nagios In Detail This book will provide you with a comprehensive series of starting points that will give you direct access to the inner workings of the latest CentOS version 7 and help you trim the learning curve to master your server. You will begin with the installation and basic configuration of CentOS 7, followed by learning how to manage your system, services and software packages. You will then gain an understanding of how to administer the file system, secure access to your server and configure various resource sharing services such as file, printer and DHCP servers across your network. Further on, we cover advanced topics such as FTP services, building your own DNS server, running database servers, and providing mail and web services. Finally, you will get a deep understanding of SELinux and you will learn how to work with Docker operating-system virtualization and how to monitor your IT infrastructure with Nagios. By the end of this book, you will have a fair understanding of all the aspects of configuring, implementing and administering CentOS 7 Linux server and how to put it in control. Style and approach This book is a practical reference guide with hands-on examples and solutions to real-world administration problems. It covers in-depth and comprehensive information on CentOS 7 and its new features.




Foundations of CentOS Linux


Book Description

You need to maintain clients, servers and networks, while acquiring new skills. Foundations of Cent OS Linux: Enterprise Linux On the Cheap covers a free, unencumbered Linux operating system within the Red Hat lineage, but it does not assume you have a Red Hat Enterprise Linux license. Now you can learn CentOS Linux, the most powerful and popular of all Red Hat clones, keep maintaining your network at work, and become an Red Hat Certified Engineer, all just for the cost of this book. Introduces CentOS Linux and Fedora clients as equals to Red Hat Enterprise Linux Sets up CentOS as a secure, high–performance web services back end Prepares you for the RHCE examination, but does not assume an RHEL installation




CentOS High Performance


Book Description

Create high availability clusters to enhance system performance using CentOS 7 About This Book Master the concepts of high performance and high availability to eliminate performance bottlenecks Maximize the uptime of services running in a CentOS 7 cluster A step-by-step guide that will provide knowledge of methods and approaches to optimize the performance of CentOS clusters Who This Book Is For This book is targeted at system administrators: those who want a detailed, step-by-step guide to learn how to set up a high-availability CentOS 7 cluster, and those who are looking for a reference book to help them learn or refresh the necessary skills to ensure their systems and respective resources are utilized optimally. No previous knowledge of high-availability systems is needed, though the reader is expected to have at least some degree of familiarity with any spin-off of the Fedora family of Linux distributions, preferably CentOS. What You Will Learn Install a CentOS 7 cluster and network infrastructure Configure firewall, networking, and clustering services and settings Set up and test a HAC (high-availability cluster) to host an Apache web server and a MariaDB database server Monitor performance and availability Identify bottlenecks and troubleshoot issues Improve performance and ensure high availability In Detail CentOS is the enterprise level Linux OS, which is 100% binary compatible to Red Hat Enterprise Linux (RHEL). It acts as a free alternative to RedHat's commercial Linux offering, with only a change in the branding. A high performance cluster consists in a group of computers that work together as one set parallel, hence minimizing or eliminating the downtime of critical services and enhancing the performance of the application. Starting with the basic principles of clustering, you will learn the necessary steps to install a cluster with two CentOS 7 servers. We will then set up and configure the basic required network infrastructure and clustering services. Further, you will learn how to take a proactive approach to the split-brain issue by configuring the failover and fencing of the cluster as a whole and the quorum of each node individually. Further, we will be setting up HAC and HPC clusters as a web server and a database server. You will also master the art of monitoring performance and availability, identifying bottlenecks, and exploring troubleshooting techniques. At the end of the book, you'll review performance-tuning techniques for the recently installed cluster, test performance using a payload simulation, and learn the necessary skills to ensure that the systems, and the corresponding resources and services, are being utilized to their best capacity. Style and approach An easy-to-follow and step-by-step guide with hands-on instructions to set up real-world simple cluster scenarios that will start you on the path to building more complex applications on your own.




CentOS Quick Start Guide


Book Description

A concise walk-through of CentOS 7, starting from installation to securing it’s environment. Key FeaturesNo previous Linux environment experience needed for reading this bookGet comfortable with a popular and stable Red Hat Enterprise Linux distributionMost of the command line based concepts are explained with graphicsBook Description Linux kernel development has been the worlds largest collaborative project to date. With this practical guide, you will learn Linux through one of its most popular and stable distributions. This book will introduce you to essential Linux skills using CentOS 7. It describes how a Linux system is organized, and will introduce you to key command-line concepts you can practice on your own. It will guide you in performing basic system administration tasks and day-to-day operations in a Linux environment. You will learn core system administration skills for managing a system running CentOS 7 or a similar operating system, such as RHEL 7, Scientific Linux, and Oracle Linux. You will be able to perform installation, establish network connectivity and user and process management, modify file permissions, manage text files using the command line, and implement basic security administration after covering this book. By the end of this book, you will have a solid understanding of working with Linux using the command line. What you will learnUnderstand file system hierarchy and essential command-line skillsUse Vi editor, I/O redirections and how to work with common text manipulating toolsCreate, delete, modify user accounts and manage passwords and their aging policyManage file ownership, permissions, and ACLExecute process management and monitoring on the command lineValidate and manage network configuration using nmcliManage remote logins using SSH and file transfer using SCP and RsyncUnderstand system logging, how to control system services with systemd and systemctl, and manage firewalIdWho this book is for Any individual who wants to learn how to use Linux as server or desktop in his environment. Whether you are a developer, budding system administrator, or tech lover with no previous Linux administration background, you will be able to start your journey in Linux using CentOS 7 with this book.




Learn CentOS Linux Network Services


Book Description

Learn to set up the latest CentOS Linux network services including DNS, DHCP, SSH and VNC, Web, FTP, Mail, Firewall, and LDAP, enabling you to provide these services on your own network. CentOS continues to be a popular Linux distribution choice, and setting up your own services is a key skill for anyone maintaining a CentOS network. You will learn how to install CentOS, and manage basic administration. You’ll then move onto understanding networking, and how to set up your required services. Each chapter is written in an easy-to-digest format and teaches you how set up, manage, and troubleshoot each service. You’ll be running your own network in no time at all. What You Will Learn Install and set up the latest version of CentOS Configure and manage a wide range of network services Solve problems remotely and manage your network efficiently Who This Book Is For Anyone who wants to learn how to set up and manage CentOS Linux network services. Some previous Linux experience is beneficial, but this book is designed to be used by beginners.




Red Hat Enterprise Linux Troubleshooting Guide


Book Description

Identify, capture and resolve common issues faced by Red Hat Enterprise Linux administrators using best practices and advanced troubleshooting techniques About This Book Develop a strong understanding of the base tools available within Red Hat Enterprise Linux (RHEL) and how to utilize these tools to troubleshoot and resolve real-world issues Gain hidden tips and techniques to help you quickly detect the reason for poor network/storage performance Troubleshoot your RHEL to isolate problems using this example-oriented guide full of real-world solutions Who This Book Is For If you have a basic knowledge of Linux from administration or consultant experience and wish to add to your Red Hat Enterprise Linux troubleshooting skills, then this book is ideal for you. The ability to navigate and use basic Linux commands is expected. What You Will Learn Identify issues that need rapid resolution against long term root cause analysis Discover commands for testing network connectivity such as telnet, netstat, ping, ip and curl Spot performance issues with commands such as top, ps, free, iostat, and vmstat Use tcpdump for traffic analysis Repair a degraded file system and rebuild a software raid Identify and troubleshoot hardware issues using dmesg Troubleshoot custom applications with strace and knowledge of Linux resource limitations In Detail 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. Style and approach This is an easy-to-follow guide packed with examples of real-world core Linux concepts. All the topics are presented in detail while you're performing the actual troubleshooting steps.




CentOS 8 Essentials


Book Description

Arguably one of the most highly regarded and widely used enterprise level operating systems available today is the CentOS 8 distribution. Not only is it considered to be among the most stable and reliable operating systems, it is also backed by the considerable resources and technical skills of Red Hat, Inc. CentOS 8 Essentials is designed to provide detailed information on the installation, use and administration of the CentOS 8 distribution. For beginners, the book covers topics such as operating system installation, the basics of the GNOME desktop environment, configuring email and web servers and installing packages and system updates using App Streams. Additional installation topics such as dual booting with Microsoft Windows are also covered, together with all important security topics such as configuring a firewall and user and group administration. For the experienced user, topics such as remote desktop access, the Cockpit web interface, logical volume management (LVM), disk partitioning, swap management, KVM virtualization, Secure Shell (SSH), Linux Containers and file sharing using both Samba and NFS are covered in detail to provide a thorough overview of this enterprise class operating system.