Configuring your service to run in a container
As we know, services are made up of source code and configurations. A service written in Java, for instance, can be packaged as a Java Archive (JAR) file containing compiled class files in Java bytecode, as well as resources such as configuration and properties files. Once packaged, the JAR file can then be executed on any machine running a Java Virtual Machine (JVM).
In order for this to work, however, the machine that we want to run our service on must have a JVM installed. Oftentimes, it must be a specific version of the JVM. Additionally, the machine might need to have some other utilities installed, or it might need access to a shared filesystem. While these are not parts of the service themselves, they do make up what we refer to as the runtime environment of the service.
Linux containers are a technology that allow developers to package an application or service with its complete runtime environment. Containers separate out the runtime...