Companies that need to deliver applications quickly and efficiently—and today, what company doesn’t need to do this?— are turning to Linux containers. What they are also finding is that once they get past the “let’s see how these container things work” stage, they are going to end up with a lot of containers running in a lot of different places.
Linux container technology is not new, but it has increased in popularity due to factors including the innovative packaging format (now ) originally invented by Docker, as well as the competitive requirement for continual development and deployment of new applications. In a May 2016 Forrester study commissioned by Red Hat, 48 percent of respondents said they were already using containers in development, a figure projected to rise to 53 percent this year. Only one-fifth of respondents said that they wouldn’t leverage containers in development processes in 2017.
Like Lego blocks, container images enable easy reuse of code and services. Each container image is like a separate Lego block, designed to do one part of the job really well. This could be a database, a data store, or even a booking service, or analytics service. By packaging each part separately, they can be used in different applications. But, without some sort of application definition (the instruction booklet), it’s difficult to create copies of the full application in different environments. That’s where container orchestration comes in.
Container orchestration provides an infrastructure like the Lego system – the developer can provide simple instructions for how to build the application. The orchestration engine will know how to run it. This makes it easy to create multiple copies of the same application, spanning developer laptops, CI/CD system, and even production data centers and cloud provider environments.