Containerization explained

Containers are lightweight, resource-efficient, and portable. They share a single host operating system (OS) with other containers — sometimes hundreds or even thousands of them. By isolating the software code from the operating environment, developers can build applications on one host OS — for example, Linux — and deploy it in Windows without worrying about configuration issues during deployment.

Containerization has been gaining wider adoption recently and is expected to become a significant tool in global enterprises. Gartner predicts that in 2022, containers will be used at more than 75% of global enterprises — up from 30% in 2020 — and that by 2024, as many as 15% of enterprise applications will run in a containerized environment. IT teams have been eager to take advantage of containers because they:

• Can be developed quickly, without concerns about their underlying environments.
• Run efficiently, using only the resources they need.
• Are written once and deployed wherever the enterprise wants to run them.

Companies such as Red Hat are developing container platforms to take advantage of open cloud hybrid strategies. These approaches employ applications running on top of multiple environments — from bare metal to virtual machines (VMs), edge computing, and public and private cloud environments.

The idea of packaging software into isolated applications is decades old, but the adoption of containers really took hold in 2013 with the advent of Docker Engine, an open-source container runtime engine that enables containerized applications to run consistently, anywhere.

How can containerization benefit your organization?

Developers use containers to build applications faster and more securely. Packaging software in containers provides six key benefits:

• Application development speed: Containerization supports continuous development and delivery by allowing features to be developed as small, independent pieces of software that can tested and reconfigured in a container, independent of the OS. This makes the development workflow cycle faster. Developers can use familiar DevOps and agile processes and tools as well.
• Portability: The independence of a container from the environment where it will run means true “write once, deploy anywhere” capability. This saves development time and maintenance costs while improving reliability.
• Fault isolation: Since containers are isolated, if a container suffers a fault or an error, it doesn’t affect other containers. While development teams work to identify and remediate the issue in the affected container, other containers don’t suffer downtime.
• Lower overhead and costs: Because containers share an OS, they require less overhead than VMs and start up quickly whenever they’re needed. A containerized app may start in seconds, whereas a virtual machine may take minutes to start up. Lower storage and memory requirements can translate into better application performance. By running hundreds or thousands of containers in the space otherwise used by one or more virtual machines, organizations may also be able to reduce licensing fees and server costs.
• Easier management: As organizations deploy large numbers of containers, it becomes necessary to manage them at scale using container orchestration platforms. Open Container Initiative (OCI)-compliant container orchestration platforms are compatible with container engines and make it easier for operators to manage applications. Developers can use management functions such as orchestrating automated deployments and rollbacks, and load balancing at scale.
• Security: Since containers ensure by design that applications are isolated, any malicious code in one doesn’t affect the others. Using security permissions, developers and security professionals can block container access and prevent contact with non-essential resources.

Containerization vs. virtualization

Virtual machines (VMs) are environments that function as virtual computers or servers. They’re created on a physical machine and may operate locally or off premises. Compared to containers, virtual machines are much larger, include their own operating systems, and can perform functions such as emulating entire systems.

While VMs virtualize the hardware, containers virtualize the operating system, which greatly reduces the amount of storage necessary for each container.

Consequently, many containers can run in the same amount of space that a virtual machine would use. Typically, containers are measured in megabytes, while virtual machines often encompass gigabytes of space.

Containerization vs. microservices

Microservices and containerization differ from each other but work well together. Think of containers as the isolated software packages, while microservices are the technology within them that performs a specific function. To create microservices, developers choose how to break up applications into specific components. These are then placed in containers, each with their own business logic and databases. Microservices in containers have all of the advantages of containers, such as portability, fault isolation, layers of security, and more.

Using microservices, developers can work faster, testing and deploying with a greater degree of certainty that an application will work. Development teams can address specific parts of applications without affecting the entire application.

Launch applications fast with containerization

Building and deploying applications quickly, and changing them as quickly, is one of the most important competitive advantages your organization can have — but it’s also a significant challenge for IT teams. Containerization can help accelerate the process.

To learn more about containers and how to implement them at scale, take a look at our Tech Talk on this topic.

Containerization frequently asked questions