Exploring Containerization: Unveiling the Core Concepts and Technologies

Dhruv Bindra | Jan 22, 2024 min read

Containers have emerged as a revolutionary way to deploy applications, offering a unique approach to running software in an isolated environment. This isolation ensures that your application operates independently, safeguarding both the applications running on the host machine and the host machine itself. A container provides a contained space to your application where it is shielded from the external interference of the host machine or other applications running on host machines.

In the Container Jungle: Making Sense of Docker and Containers

A major confusion lies in the interchangeable use of terms like “Docker” and “Containers.” It’s crucial to clarify the misunderstanding that between Docker and broader concept of containers, as the two are distinct entities. Docker is not just a technology; it’s also a company that introduced and popularized containerization. When people refer to “Docker containers,” they may be referring to containers managed by the Docker platform. Docker provides an end-to-end solution for container development, deployment, and management. Whereas Containers existed before Docker. The concept of containers and container-like technology has been around for a long time. Docker simplified and popularized the use of containers, but it’s important to understand that containers, as a general concept, are not exclusive to Docker.

Linux Namespaces: Creating Isolated Environments

Linux namespaces are a kernel-level feature that empowers processes with isolated and separate views of specific system resources. This abstraction allows the creation of lightweight and independent environments for processes. Various namespace types, including network, mount, cgroup, user, and PID, offer isolation for distinct resources. The unshare command facilitates namespace creation, and the setns command associates processes with existing namespaces. Additionally, the chroot command changes the root directory, establishing an isolated filesystem environment.

Control Groups (cgroups): Managing Resources Dynamically

Control Groups, or cgroups, represent a crucial Linux kernel feature for allocating and managing system resources among groups of processes. In the context of containerization, cgroups are instrumental in controlling and limiting resource consumption for containerized applications. This includes dynamic adjustments to resource limits, real-time monitoring, and statistics collection. Container runtimes leverage the cgroup API to interact with the kernel, ensuring effective resource management.

Integration of Namespaces and cgroups

The synergy between Linux namespaces and cgroups is pivotal for comprehensive containerization. While namespaces provide isolation for various system resources, cgroups facilitate dynamic resource allocation and management. Together, they enable the creation of isolated, resource-controlled environments for applications. This integration forms the foundation for container runtimes, empowering developers with efficient and portable solutions for deploying and managing software.


In conclusion, Linux namespaces and cgroups are integral components of containerization, offering a robust framework for creating isolated and resource-controlled environments. Understanding the interplay between these kernel features provides developers and operators with insights into building efficient and scalable containerized solutions in today’s dynamic computing landscape.