Introduction

All online businesses need to account for growth. As a business receives more visitors to its site, the underlying infrastructure needs to scale to provide the same level of performance that the visitors are accustomed to. Horizontal scaling, the addition of more servers rather than increasing the power of the existing servers, is an easy way to build our web servers’ ability to handle a more significant amount of traffic and protect us against hardware failure. Ensuring that the additional web servers have the same files and data is a potentially time-consuming and challenging task. Automating that task using free, open-source software, such as lsyncd, is a way to ensure that we have a safe, secure, and repeatable method of copying files from one server to another.