2. Technical Overview

The whole system will be built on GNU/Linux, and Docker will be used for deployment of Internet apps. We will deploy most apps in Docker containers, which run on top of the host system. We use Docker for the reason that a Docker container can isolate the app in it from other parts of the system, which usually leads to easy deployment, and better security. A typical deployment structure for an app is illustrated in Fig. 2.1.

Overview of the deployment structure.

Fig. 2.1 Overview of the deployment structure is shown.

As shown in Fig. 2.1, software in each box runs inside a Docker container, except for Postfix which runs on the host. Containers locate each other via the dnsmasq server on the host (not shown in Fig. 2.1). Note that not all Internet apps have the complete structure as shown in Fig. 2.1, e.g., the XMPP/Jabber server software Prosody is not a web service thus Nginx is not part of the game—users send requests directly to the Prosody instance.

Throughout this manual, GNU Bash is assumed to be the shell used on the host.