Microservices and containers
There is no direct relationship between microservices and containers. Microservices can run without containers, and containers can run monolithic applications. However, there is a sweet spot between microservices and containers.
Containers are good for monolithic applications, but the complexities and the size of the monolith application may kill some of the benefits of the containers. For example, spinning new containers quickly may not be easy with monolithic applications. In addition to this, monolithic applications generally have local environment dependencies, such as the local disk, stovepipe dependencies with other systems, and so on. Such applications are difficult to manage with container technologies. This is where microservices go hand in hand with containers.
The following diagram shows three polyglot microservices running on the same host machine and sharing the same operating system but abstracting the runtime environment:
The real advantage of containers...
