Book Image

Mastering CentOS 7 Linux Server

By : Mohamed Alibi, BHASKARJYOTI ROY
Book Image

Mastering CentOS 7 Linux Server

By: Mohamed Alibi, BHASKARJYOTI ROY

Overview of this book

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.
Table of Contents (16 chapters)
Mastering CentOS 7 Linux Server
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

SSH key-based authentication


As we have noticed by using SSH every time, we need to type the password, which is not something recommended in many security policies. This is where we will use the SSH feature to use authentication by using public/private keys.

SSH provides a tool for creating public/private keys to use for remote connection authentication, without the need to use a password. How do we do that? It's simple. For this test example we are going to create a new RSA key, a little bit more secure than the usual (we can create different types of keys such as dsa, ecdsa, ed25519):

$ ssh-keygen –t rsa -b 2048 -v

Then we follow the steps presented by the command. For a default installation, we can just keep typing Enter. Otherwise, we can always add some kind of passphrase to make it more secure. We may need to specify the key file name so we can use it later.

Then we need to copy the newly created keys file to the host that we want to connect to. There are two ways of doing this. The...