What Are Containers?
Containers can be defined as an efficient way of developing and deploying applications. Containers provide an organized packaging system though which the applications can be extracted from the environment in which they are operating. This decoupling method enables the applications based in the containers to be deployed consistently and easily irrespective of whether the target environment is a public cloud, a private data center or the personal laptop of a developer. A cloud hosting platform enables containerization of the applications, it is possible to attain a clean separation of all the aspects. This enables the developers to concentrate on application logic and dependencies and the IT operation teams can concentrate on the deployment and management aspects without worrying over application specifications like particular software versions and configurations specific to the application etc.
For those utilizing the virtualized environments, containers are usually compared with virtual machines (VM). A VM is a guest operating system like Windows or Linux that operates on top of a host operating system with a virtual access to the underlying hardware. Similar to the virtual machines, with the use of containers developers can club the application together along with the libraries and dependencies. The similarities finish as the containers offer a lightweight unit for the developers and the IT Ops teams to work with thus ensuring many benefits.
The Google Way Of Using Containers
Google operates everything in containers right from Gmail to YouTube to Google Search. Containerization enables the development teams work, deploy the software more efficiently and function at an unpredictable scale. Every week Google starts over 2 million containers. Google has a great experience in terms of running containerized workloads and they have shared all the knowledge and information with the community.
Why Containers?
The approach of virtual machines is to virtualize the hardware stack and on the other hand, containers virtualize at the operating system level with multiple containers operating directly on the OS kernel. This implies that containers are more lightweight: they share the OS kernel; they start faster and utilize only a fraction of memory as compared to booting of a complete OS.
Containers are available in many formats. Among all the formats, the Docker container is a commonly used. Docker is an open-source container that is also supported on the Google Cloud platform and by the Google Kubernetes engine.
Consistent And Reliable Environment
Through containers, developers get the ability to create predictable and isolated environments for their applications. Containers can also incorporate the software dependencies required for the application like some particular versions of the programming language runtimes and software libraries. If we look at it from a developer’s viewpoint, all these aspects are guaranteed to be consistent irrespective of whether the application is deployed on time or if it is untimely deployed. higher productivity is ensured as the developers and IT Ops teams will have to spend less time in debugging and analyzing the differences in environments and they can concentrate more on ensuring new functionalities for the users. This results in a fewer bugs as the developers get the ability of making assumptions for the dev and test environments and they can be sure that the assumptions will hold true in production.
Operate Anywhere
One of the best things about containers is that they can be operated virtually anywhere and this simplifies the process of development and deployment to a great extent on Linux, Windows and Mac operating systems, on the virtual machines, on bare metal, on the developer’s machine or in the data center premises and in the public cloud as well. The Docker image format is an extensively popular format for the containers that further helps with portability. you can use containers and run your software wherever you want.
Isolation
Factors like CPU, storage, memory and network resources are all virtualized in the containers at the OS-level. This helps in providing the developers to get a better insight about the OS that is perfectly isolated from the other applications.
Container Benefits |
Virtual Machine Benefits |
|
Consistent Routine Environments |
✓ |
✓ |
Application Sandboxing |
✓
|
✓ |
Small Size On Disk |
✓ |
|
Low Overhead |
✓ |
From Code To Applications
With containers you can package your application along with its dependencies into a compact format that can be controlled through version; thereby, enabling easy replication of your application with all the developers of your team and with all the machines in your cluster.
Just like the way in which the software libraries package parts of code together that enables the developers to abstract logic on aspects like user authentication and session management; containers enable your application to be packaged completely by abstracting the operating system, the machine and the code. As the containers are based on a service-based architecture, the complete unit the developers are supposed to work on reduces in size thus resulting in higher agility and productivity. All this helps in easing the aspects like testing, development, deployment and the overall management of your applications.
Monolithic To Service Based Architecture
Containers work best when it comes to service based architectures contrary to the monolithic architectures where every part of the application is interconnected right from IO to data processing to rendering; the service based architecture separates these aspects into individual components. The separation and division of labor enables the services to go on consistently even if the others are failing this making sure that your application is more reliable.
With the help of componentization you can develop applications faster and with more reliability. It is easy to deal with smaller codebases and because the services are separated, testing some specific inputs and outputs also becomes easier.
Containers are ideal for the service based applications as it is possible to health check every container, limit each service to particular resources and stop the services independently from each other.
Containers extract the code right away, this enables the users to deal with separate services like black boxes; this further reduces the space required by the developers. When the developers need to work on services that depend on other, they can easily start a container for a specific service without putting a lot of time in setting up the environment and without doing any troubleshooting in advance.