Book Image

Practical Linux Security Cookbook - Second Edition

By : Tajinder Kalsi
Book Image

Practical Linux Security Cookbook - Second Edition

By: Tajinder Kalsi

Overview of this book

Over the last few years, system security has gained a lot of momentum and software professionals are focusing heavily on it. Linux is often treated as a highly secure operating system. However, the reality is that Linux has its share of security ?aws, and these security ?aws allow attackers to get into your system and modify or even destroy your important data. But there’s no need to panic, since there are various mechanisms by which these ?aws can be removed, and this book will help you learn about different types of Linux security to create a more secure Linux system. With a step-by-step recipe approach, the book starts by introducing you to various threats to Linux systems. Then, this book will walk you through customizing the Linux kernel and securing local files. Next, you will move on to managing user authentication both locally and remotely and mitigating network attacks. Later, you will learn about application security and kernel vulnerabilities. You will also learn about patching Bash vulnerability, packet filtering, handling incidents, and monitoring system logs. Finally, you will learn about auditing using system services and performing vulnerability scanning on Linux. By the end of this book, you will be able to secure your Linux systems and create a robust environment.
Table of Contents (20 chapters)
Title Page
Copyright and Credits
Contributors
Packt Upsell
Preface
Index

Network monitoring using OpenNMS


When we want to monitor unlimited devices in our network at a single instance, we can use OpenNMS. It's an open source and free network monitoring web application system and helps in detecting and monitoring services or nodes automatically in the network. More devices or nodes can also be added to OpenNMS easily.

Getting ready

To configure OpenNMS, we will be using the Ubuntu server, which has been updated to the latest stable version. Once we are done with updating the server, we need to make a few configurations to get our system ready for installing and configuring OpenNMS:

  1. To begin, we will edit the /etc/hosts file to set a proper and fully qualified domain name for our server:

Here, we have added example.OpenNMS.local as the domain name for our server.

  1. Next, we edit /etc/hostname and update the same domain name:
  1. OpenNMS uses PostgreSQL for its database purposes. Hence, we will install PostgreSQL using the following command:
  1. Once the installation completes,...