What is Docker : Its Uses and Purpose
Docker is an open-source software platform which is used to create, deploy and cope virtualized application containers upon a common operating system with the assistance of an ecosystem of allied tools. Docker Inc., the firm which originally found Docker that supports a commercial edition and it is the principal sponsor of the open-source tool.
In addition to this, a docker is a tool that packages, provisions and runs containers independent of the operating system. The Container technology is available with the help of OS; it packages the application service or function with all of the libraries, dependencies, configuration files as well as other important parts to operate. In this process, each container shares the services of one underlying operating system.
Docker was developed to work on the Linux platform, but has explored to offer huge support for non-Linux OS. Involving – Apple OS X and Microsoft Windows. Its versions are available in the market, i.e. Amazon web services, and Microsoft Azure.
- It consists of various main components. Docker Community Edition is an open-source, while Docker Enterprise Edition is a version rendered by Docker Inc., its version include Basic, Standard, and Advanced.
- The Docker Engine is a fundamental client-server tool which aids container technology in order to manage tasks and flow of work in preparing container-based applications. It creates a server-side daemon process which is responsible for managing images, networks, containers, and storage volumes. The daemon also explores a client-side command line interface which allows customers to get in touch to interact with daemon with the assistance of the Docker application programming interface. Containers are developed via Dockers are also known as – Dockerfiles. It’s associated files define the composition of components in Docker container.
- Docker Hub is software as a service tool which makes users’ ability to publish and transfer container-based application from a common library. This service touts 100000+ publically available applications for public and private registries.
- Docker swarm mode in Docker Engine which supports cluster load balancing for Docker. With this mode, variety Docker host resources are combined together in order to act as one. It enables users’ to quickly scale up container deployments for several hosts.
Docker Alternatives, Ecosystem, and Standardization
There are numerous third party tools that work with Docker for tasks likewise- container management and clustering. Furthermore, the Docker ecosystem encompasses an intermixture of open source and proprietary techniques, i.e. open source Kubernetes. Along with this, Docker not only a container platform available but it also holds a wide range of container’s marketplace. One of the greater competitors of docker is CoreOS rkt, pronounced rocket. Basically, it is known for its security that also supports SELinux and trusted platform management.
Docker is an open-source and community-supported, but there is an initiative to more formally standardize container distribution and packaging. The fundamental effort is embodied in OCI is the establishment of a foster common container format and runtime environment. Docker Inc. has the main role in OCI but they share membership with other container industry vendors includes- Intel, AWS, Red Hat, Virtuozzo, etc.
Docker Advantages and Disadvantages:
Benefits of Docker
- Return on investment and cost savings- The prime advantage of Docker is ROI. Especially for multinational and large companies which needs to generate steady revenue across the long term, the solution can be better only if it can drive low cost while increasing profits.
- Rapid development- It can reduce deployment to seconds because of Docker create a container for all processes and even does not boot an OS. So, it would be higher than what is affordable without worrying about the cost to bring it up again. Data can be created and destroyed as well.
- Security- Docker ensures that applications which are running on containers are entirely segregated and isolated from each other. From a security perspective, it grants complete control over traffic flow and management.
- Continuous integration- When it comes to continuous integration, Docker works properly along with tools likewise- Jenkins, Wercker, and Travis. Such tools can never save the new version as a Docker image, every time source code is updated, users can tag it with a version number and push to Docker Hub; at last deploy to production.
Limitations of Docker
- Missing features- There are huge features requests are in the process like – container self-registration, self-inspects and copying files from the hosts to the container and so on.
- Data in the container- There is the time when a container goes down, so after that, it requires a backup and recovery strategy. Although, developers have numerous solutions for that they aren’t automated or not so scalable yet.
- Run applications as fast as a bare metal serve- In comparison with virtual machines, Docker containers carry low overhead but not zero. For example- if we run any application directly over bare-metal server we will get true bare-metal speed even without using containers or virtual machines.
- Provide cross-platform compatibility- If an application is designed, the major issue is to run in a Docker on Windows then it can’t run on Linux or Vice Versa. As virtual machines aren’t subject to these limitations, it makes Docker less attractive or efficient in a certain highly heterogeneous environment that is composed for both Linux and Windows Servers.
- Run applications with graphical interfaces- In general, Docker is formulated for hosting applications that run over the command line. However, we have certain ways through which we can make it possible to run a graphical interface inside a Docker container; it is clunky. Hence, it can be said that Docker isn’t a good solution for application which needs wider interfaces.
So, if you are planning to Docker such points should be kept in mind. Docker is not the best choice for application deployment invariably, in many cases traditional virtual machines or bare-metal servers are good solutions.