Container Technology

Container

A container is a standardized software unit that includes all the necessary dependencies to run an application reliably and quickly in different computing environments. Docker container images are lightweight, standalone, and executable packages of software that contain the code, runtime, system tools, system libraries, and settings required to run an application.

Container images are transformed into containers during runtime. In the case of Docker containers, images become containers when they are executed on Docker Engine. Containerized software is available for both Linux and Windows-based applications, and it ensures that the software runs uniformly, regardless of the infrastructure. Containers create a barrier between the software and its environment, which guarantees that it operates consistently, even when there are differences between development and staging. Overall, containers offer a reliable and efficient way to run software in any environment.


Linux Container

Linux containers represent the next step in the evolution of application development, deployment, and management. They offer portability and version control for container images, ensuring that what works on a developer's machine will also work in production. Golden images, a specific type of container image, create a consistent and reliable baseline for system configuration. Compared to virtual machines, running Linux containers are more efficient in terms of resource usage, have a standard interface, and retain application isolation, making them easier to manage as part of a larger application system comprising multiple containers.

Containers Vs. Virtualization

Virtualization provides the biggest benefit of cost savings. Running multiple virtual machines on a single physical server saves money and space, while maximizing resource utilization and flexibility. It eliminates server idleness and enables easy creation, destruction, and migration of VMs between hosts. This makes it simpler to scale and manage computing resources and implement disaster recovery plans.

Containers offer several advantages, including their high density and efficiency. Running multiple container instances provides the benefits of bare-metal performance. Additionally, containers allow you to deploy your applications quickly, consistently, and with greater portability since all dependencies are already packaged within the container. This also means that users only have to maintain a single operating system while getting the most out of their infrastructure resources without compromising scalability.


Here are some of the top benefits of containers for business.
  • Agility and productivity 
  • Consistency 
  • Scalability and optimization of the infrastructure 
  • Resilience 
  • Portability  

Docker

Docker is a platform that allows developers to create, deploy, and manage containers. These containers are standardized executable components that combine the application source code with the operating system libraries and dependencies. This enables the code to be run in any environment, making it easier to build, update, and manage applications.

Although the software itself is relatively simple to learn, Docker-specific terminology can be confusing for new users. Terms like Dockerfiles, images, containers, volumes, and others may need to be mastered and should become second nature over time. Therefore, it is advisable to understand the basic roles of these elements as it can significantly speed up the learning process of working with them.


Terminology

A Dockerfile is a text document that provides instructions for building a Docker image. It outlines the base image to use, the software to install, the configuration to apply, and the commands to run to create the final image.

Docker Hub is a cloud-based registry service specifically designed for Docker images. It enables users to store, share, and deploy Docker images effortlessly. Known as the world's largest container registry, Docker Hub has a vast collection of 18 million images with over 20 billion downloads every month.

A Docker image is a self-contained package of software including code, runtime, system tools, libraries and settings needed to run an application. Docker images are built from Dockerfiles.

A Docker container is a lightweight, isolated environment that can share the operating system kernel with other containers. It is created from a Docker image.

A Docker volume is a directory or file that can be shared between a Docker container and the host machine. Volumes are used to persist data generated by and used by Docker containers.