Book Image

Puppet 5 Cookbook - Fourth Edition

By : Thomas Uphill
Book Image

Puppet 5 Cookbook - Fourth Edition

By: Thomas Uphill

Overview of this book

Puppet is a configuration management system that automates all your IT configurations, giving you control of managing each node. Puppet 5 Cookbook will take you through Puppet's latest and most advanced features, including Docker containers, Hiera, and AWS Cloud Orchestration. Updated with the latest advancements and best practices, this book delves into various aspects of writing good Puppet code, which includes using Puppet community style, checking your manifests with puppet-lint, and learning community best practices with an emphasis on real-world implementation. You will learn to set up, install, and create your first manifests with version control, and also learn about various sysadmin tasks, including managing configuration files, using Augeas, and generating files from snippets and templates. As the book progresses, you'll explore virtual resources and use Puppet's resource scheduling and auditing features. In the concluding chapters, you'll walk through managing applications and writing your own resource types, providers, and external node classifiers. By the end of this book, you will have learned to report, log, and debug your system.
Table of Contents (16 chapters)
Title Page
Packt Upsell
Contributors
Preface
Index

Managing firewalls with iptables


In this chapter, we will begin to configure services that require communication between hosts over a network. Most Linux distributions will default to running a host-based firewall, iptables or firewalld. If you want your hosts to communicate with each other, you have two options: turn off iptables or configure iptables to allow the communication.

I prefer to leave iptables turned on and configure access. Keeping iptables is just another layer in your defence across the network. Host-based firewalls aren't a magic solution that will make your system secure, but they will block access to services you didn't intend to expose to the network.

Configuring iptables properly is a complicated task, which requires a deep understanding of networking. The example presented here is a simplification. If you are unfamiliar with iptables, I suggest you research them before continuing. More information can be found at http://wiki.centos.org/HowTos/Network/IPTables or https...