What is containerization?
Containerization is a software deployment process that bundles an application’s code with all the files and libraries it needs to run on any infrastructure. Traditionally, to run any application on your computer, you had to install the version that matched your machine’s operating system. For example, you needed to install the Windows version of a software package on a Windows machine. However, with containerization, you can create a single software package, or container, that runs on all types of devices and operating systems.
What are the benefits of containerization?
Developers use containerization to build and deploy modern applications because of the following advantages.
Software developers use containerization to deploy applications in multiple environments without rewriting the program code. They build an application once and deploy it on multiple operating systems. For example, they run the same containers on Linux and Windows operating systems. Developers also upgrade legacy application code to modern versions using containers for deployment.
Containers are lightweight software components that run efficiently. For example, a virtual machine can launch a containerized application faster because it doesn't need to boot an operating system. Therefore, software developers can easily add multiple containers for different applications on a single machine. The container cluster uses computing resources from the same shared operating system, but one container doesn't interfere with the operation of other containers.
Software development teams use containers to build fault-tolerant applications. They use multiple containers to run microservices on the cloud. Because containerized microservices operate in isolated user spaces, a single faulty container doesn't affect the other containers. This increases the resilience and availability of the application.
Containerized applications run in isolated computing environments. Software developers can troubleshoot and change the application code without interfering with the operating system, hardware, or other application services. They can shorten software release cycles and work on updates quickly with the container model.
What are containerization use cases?
The following are some use cases of containerization.
Cloud migration, or the lift-and-shift approach, is a software strategy that involves encapsulating legacy applications in containers and deploying them in a cloud computing environment. Organizations can modernize their applications without rewriting the entire software code.
Adoption of microservice architecture
Organizations seeking to build cloud applications with microservices require containerization technology. The microservice architecture is a software development approach that uses multiple, interdependent software components to deliver a functional application. Each microservice has a unique and specific function. A modern cloud application consists of multiple microservices. For example, a video streaming application might have microservices for data processing, user tracking, billing, and personalization. Containerization provides the software tool to pack microservices as deployable programs on different platforms.
Internet of Things (IoT) devices contain limited computing resources, making manual software updating a complex process. Containerization allows developers to deploy and update applications across IoT devices easily.
How does containerization work?
Containerization involves building self-sufficient software packages that perform consistently, regardless of the machines they run on. Software developers create and deploy container images—that is, files that contain the necessary information to run a containerized application. Developers use containerization tools to build container images based on the Open Container Initiative (OCI) image specification. OCI is an open-source group that provides a standardized format for creating container images. Container images are read-only and cannot be altered by the computer system.
Container images are the top layer in a containerized system that consists of the following layers.
Infrastructure is the hardware layer of the container model. It refers to the physical computer or bare-metal server that runs the containerized application.
The second layer of the containerization architecture is the operating system. Linux is a popular operating system for containerization with on-premise computers. In cloud computing, developers use cloud services such as AWS EC2 to run containerized applications.
The container engine, or container runtime, is a software program that creates containers based on the container images. It acts as an intermediary agent between the containers and the operating system, providing and managing resources that the application needs. For example, container engines can manage multiple containers on the same operating system by keeping them independent of the underlying infrastructure and each other.
Application and dependencies
The topmost layer of the containerization architecture is the application code and the other files it needs to run, such as library dependencies and related configuration files. This layer might also contain a light guest operating system that gets installed over the host operating system.
What is container orchestration?
Container orchestration is a software technology that allows the automatic management of containers. This is necessary for modern cloud application development because an application might contain thousands of microservices in their respective containers. The large number of containerized microservices makes it impossible for software developers to manage them manually.
Benefits of container orchestration
Developers use container orchestration tools to automatically start, stop, and manage containers. Container orchestrators allow developers to scale cloud applications precisely and avoid human errors. For example, you can verify that containers are deployed with adequate resources from the host platform.
What are the types of container technology?
The following are some examples of popular technologies that developers use for containerization.
Docker, or Docker Engine, is a popular open-source container runtime that allows software developers to build, deploy, and test containerized applications on various platforms. Docker containers are self-contained packages of applications and related files that are created with the Docker framework.
Linux is an open-source operating system with built-in container technology. Linux containers are self-contained environments that allow multiple Linux-based applications to run on a single host machine. Software developers use Linux containers to deploy applications that write or read large amounts of data. Linux containers do not copy the entire operating system to their virtualized environment. Instead, the containers consist of necessary functionalities allocated in the Linux namespace.
Kubernetes is a popular open-source container orchestrator that software developers use to deploy, scale, and manage a vast number of microservices. It has a declarative model that makes automating containers easier. The declarative model ensures that Kubernetes takes the appropriate action to fulfil the requirements based on the configuration files.
What is a virtual machine?
A virtual machine (VM) is a digital copy of the host machine's physical hardware and operating system. A host machine might have several VMs sharing its CPU, storage, and memory. A hypervisor, which is software that monitors VMs, allocates computing resources to all the VMs regardless of whether the applications use them.
Containerization compared to virtual machines
Containerization is a similar but improved concept of a VM. Instead of copying the hardware layer, containerization removes the operating system layer from the self-contained environment. This allows the application to run independently from the host operating system. Containerization prevents resource waste because applications are provided with the exact resources they need.
What is serverless computing?
Serverless computing refers to a cloud computing technology where the cloud vendor fully manages the server infrastructure powering an application. This means that developers and organizations do not need to configure, maintain, or provision resources on the cloud server. Serverless computing allows organizations to automatically scale computing resources according to the workload.
Containerization compared to serverless computing
Serverless computing allows instant deployment of applications because there are no dependencies such as libraries or configuration files involved. The cloud vendor doesn't charge for computing resources when the serverless application is idle. Containers, on the other hand, are more portable, giving developers complete control of the application's environment.
What is cloud native?
Cloud native is a software development method that builds, tests, and deploys an application in the cloud. The term cloud native means that the application is born and resides in a cloud computing environment. Organizations build cloud-native applications because they are highly scalable, resilient, and flexible.
Containerization compared to cloud native
Cloud-native application development requires different technologies and approaches than conventional monolithic applications. Containerization is one of the technologies that allows developers to build cloud-native applications. It works with other cloud-native technologies, such as service mesh and APIs, to allow microservices to work cohesively in a cloud-native application.
What is AWS App2Container?
AWS App2Container is a containerization tool that allows software developers to modernize legacy applications. Developers use App2Container to turn Java and .NET applications into containerized applications:
- App2Container provides standard tools for migrating existing platform-based applications to the AWS environment.
- With App2Container, developers are assured of security when scaling cloud applications.
- Developers use App2Container to simplify identifying dependencies and configurations when creating container images.
Get started with containerization on AWS by signing up for an AWS account today.
AWS Containerization next steps
Instantly get access to the AWS free tier.
Get started building with AWS in the AWS Management Console.