Hobson - Troubleshooting CentOS: a practical guide to troubleshooting the CentOS 7 community-based enterprise server

Jonathan Hobson is a professional Dev/Ops engineer who provides round-the-clock application and server support to one of the world's largest online newspapers. He has been using CentOS since its inception, and as the author of the best-selling CentOS 6 Linux Server Cookbook , Packt Publishing (ISBN-13: 978-1849519021), Jonathan maintains a strong reputation for the generation of ideas, problem solving, building business confidence, and finding innovative solutions in challenging environments.

Jonathan has worked in a variety of environments, and with more than 20 years of experience as a professional developer, database administrator, and server engineer, he continues to support the open source community at large.

Following a wide range of interests beyond the computer screen, Jonathan also enjoys walking his dogs and getting out and about in the great outdoors.

This book is dedicated to those I love and the things I have achieved. A new story has just begun.

Mohamed Alibi is a system and network administrator for bioinformatics research computer infrastructure at the Institut Pasteur de Tunis. He received his master's degree diploma in network system and telecommunication from the Faculty of Sciences, Tunis El-Manar. His did his master's graduation internship at the University of Illinois at Urbana-Champaign (United States) from the National Center for Supercomputing Applications and the Institution for Genomic Biology, where he helped develop and adapt a data transfer solution to be used in bioinformatics research centers across Africa.

He started his career in 2011 as a technical support assistant and was promoted in 2012. He is currently part of a network project called H3ABioNet that helps African nodes enhance their bio-informatics research capacities. He was the co-chair of the Infrastructure Working Group, a group that helps to develop and enhance the computer infrastructure of project nodes. Since 2015, he has been training at the technical workshops held at the University of Pretoria (South Africa) as a system administrator of the African Nodes. Since 2014, he has also been a computer science professor at the Higher Institute of Biotechnology of Sidi Thabet.

I would like to acknowledge my family for their constant support and my friends and colleagues for helping me make better decisions. Finally, I would like to thank the H3ABioNet Consortium for giving me the opportunity to expand my knowledge and experience to be capable of doing this work.

Toni de la Fuente is the principal solutions engineer for the Americas at Alfresco. He is the author of Backup and Disaster Recovery White Paper and Alfresco Security Best Practices .

He has more than 17 years of experience in security architecture, systems administration, ECM architecture, cloud computing, and monitoring and scalability projects. He has a variety of certifications, such as the LPI Linux certification, Red Hat Certified Engineer (RHCE), ITIL v3, and an AWS Certified Solutions Architect. Recently, he did an advanced training course in computer forensics and is a collaborator to the UOC University.

Toni is a declared open source enthusiast and computer security lover, having founded phpRADmin, a security open source project in 2006 and Alfresco BART (a backup tool). He has participated in other open source-related projects, such as Madrid Wireless, Linux Fedora, OpenSolaris Hispano, and multiple Alfresco-related plugins, such as the Nagios plugin. His name is mentioned in different books on network security, among others. He regularly teaches, conducts lectures, courses, and conferences in events in Europe, the United States, and Latin America. He has also contributed to the world of open source for more than 13 years with his blog at http://byx.com and through Twitter at https://twitter.com/toniblyx.

This is the third book he has contributed to Packt Publishing. We also collaborated with him on Building a Home Security System with BeagleBone and Icinga Network Monitoring .

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Preface

CentOS (Community Enterprise Operating System) is known as a robust, stable, and generally trouble-free operating system that is particularly well-suited to the role of a server. As a faithful adaption of RHEL, CentOS has been with us since its initial release in May 2004. It is used by a significant number of servers across the world, by an increasing number of individuals and businesses for a variety of needs, and it can be found in many mission critical situations. CentOS is considered to be a favorite among Linux professionals, and if it is configured correctly, serviced, and maintained, in most instances, a CentOS-based server should never give rise to any major complications. However, there are occasions when things do go wrong, and in such a situation, where the old joke of "rebooting the machine" is not the most appropriate form of action, then your only recourse is to consider troubleshooting the system.