Containerization is

operating system-level virtualization OS-level virtualization is an operating system (OS) paradigm in which the kernel allows the existence of multiple isolated user space instances, called ''containers'' ( LXC, Solaris containers, Docker, Podman), ''zones'' (Solaris containers), ' ...

or application-level virtualization over multiple network resources so that software applications can run in isolated user spaces called ''containers'' in any

cloud In meteorology, a cloud is an aerosol consisting of a visible mass of miniature liquid droplets, frozen crystals, or other particles suspended in the atmosphere of a planetary body or similar space. Water or various other chemicals may ...

or non-cloud environment, regardless of type or vendor.

Usage

The ''containers'' are basically a fully functional and portable cloud or non-cloud computing environment surrounding the application and keeping it independent from other parallelly running environments. Individually each container simulates a different software application and runs isolated processes by bundling related configuration files, libraries and dependencies. But, collectively multiple containers share a common OS Kernel. In recent times, the containerization technology has vastly adopted by cloud computing platforms like

Amazon Web Services Amazon Web Services, Inc. (AWS) is a subsidiary of Amazon that provides on-demand cloud computing platforms and APIs to individuals, companies, and governments, on a metered pay-as-you-go basis. These cloud computing web services provide d ...

, Microsoft Azure, Google Cloud Platform, and

IBM Cloud IBM Cloud, (formerly known as Bluemix) is a set of cloud computing services for business offered by the information technology company IBM. Services As of 2021, IBM Cloud contains more than 170 services including compute, storage, networki ...

. Containerization has also been pursued by the U.S. Department of Defense as a way of more rapidly developing and fielding software updates, with first application in its

F-22 The Lockheed Martin F-22 Raptor is an American single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). As the result of the USAF's Advanced Tactical Fighter (ATF) program, the ...

air superiority fighter.

Types of containers

* OS containers * Apps containers

Security issues

*Because of common OS, security threats can affect the whole containerized system. *In containerized environments, security scanners generally protect the OS but not the application containers, which adds unwanted vulnerability.

Container management, orchestration, clustering

Container orchestration or container management is mostly used in the context of application containers. Implementations providing such an orchestration include

Kubernetes Kubernetes (, commonly stylized as K8s) is an open-source container orchestration system for automating software deployment, scaling, and management. Google originally designed Kubernetes, but the Cloud Native Computing Foundation now maintains ...

and Docker swarm.

Container cluster management

Container clusters need to be managed. This includes functionality to create a cluster, to upgrade the software or repair it, balance the load between existing instances, scale by starting or stopping instances to adapt to the number of users, to log activities and monitor produced logs or the application itself by querying sensors. Open-source implementations of such software include OKD and Rancher. Quite a number of companies provide container cluster management as a managed service, like Alibaba, Amazon, Google, Microsoft.

References

Cloud computing {{computer-stub

Usage

Types of containers

Security issues

Container management, orchestration, clustering

Container cluster management

Further reading

Journal articles

Books

See also

References