If you are a software developer, you must have heard of Docker. Docker is an open-source platform that helps developers deliver software in packages called “containers” using operating system-level virtualization capabilities. If you are interested in this area, in this article from the ded9 blog, we want to explain what Docker is. We’ll also talk about other important concepts such as containers, tools, Docker terminology, and Docker functionality. Note that in order for this article to be more useful to you, you need to be familiar with some basic Docker concepts.
What is Docker and what are its uses?
As we said in the introduction of this article, Docker is an open-source platform for building, deploying, and managing container applications. Using this tool, developers can build containers and deploy, run, update, and manage them. This tool also allows developers to run components that combine source code with operating system libraries and dependencies to run that code in any environment.
Along these lines, containers are also tasked with making the development and delivery of distributed applications easier. The use of these tools has become more popular; Especially now that organizations are moving towards cloud-native development and the use of hybrid multi-cloud environments. Although it is possible for developers to build containers without using Docker and with capabilities available on Linux Server and other operating systems, using Docker to build containers is faster, easier, and more secure. The proof of this is Docker’s own report. According to this report, more than 13 million developers worldwide use this open-source platform!
What is a container and what are the advantages of using it?
Considering that containers are an integral part of Docker, we want to examine them more closely.
1. Container and its concept
Containers are a form of operating system virtualization. A single container may be used to run anything from a small microservice or software process to a larger application. In each container, all executable files, binary codes, libraries, and files needed for configuration are located. However, compared to the server or machine virtualization approach, containers do not contain an OS image. This makes the containers smaller and, in addition to easier transportation, lower overhead costs.
In larger application deployments, multiple containers may be deployed in batches. Such large clusters are typically managed by container orchestrators such as Kubernetes. In general, it can be said that containers have all the functions and advantages of virtual machines; including program isolation scalability and cost-effectiveness.
2. Advantages of using containers
Containers are a simple way to build, test, deploy, and redeploy applications in various environments, from laptops to on-premise data centers and even the cloud. The following are among the advantages of using containers:
- Less overhead: Containers require fewer system resources than traditional or hardware virtual machine environments because they are not OS images.
- Portability: Applications running in containers can be easily deployed across different operating systems and hardware platforms.
- More consistent performance: DevOps teams are well aware that containerized applications will run exactly the same regardless of where they are deployed.
- Greater performance: Containers allow applications to be deployed faster. Scaling them will also be much faster using containers.
- Better application development: Containers support Agile and DevOps to accelerate application development testing and production cycles.
Why use Docker?
In a world where technology continues to develop at a breakneck speed, all services provided to customers through the Internet platform need a miracle that helps to minimize deployment time and use the minimum resources of your systems. Docker is the miracle that provides these capabilities. In addition, Docker is open source and this is another important feature of this platform. Next, we mention eight important reasons that will convince you to use Docker.
1. Ease of use
Docker’s main motto is “Docker For Everyone!” This claim is based on the fact that learning Docker is very simple and that it is easy to use. Even non-technical people can get Docker projects up and running with just a few commands.
2. Environmental isolation
Before Docker, configuring the environment for different software versions on the same machine was one of the major problems for developers; But now you can create an isolated environment called Docker Container for each version of the application. With this feature, each container has its own isolated environment configuration, none of which affects the configuration of the operating system or any other containers running on your machine at the same time.
3. Independence from operating systems
One of the important features of using Docker is that it makes the developer independent from the operating system; Therefore, running Docker on different operating systems, from Linux to Windows or even ARM-based platforms, is not that different.
4. Rapid development and deployment
Docker helps developers save time by automating most repetitive tasks; Of course, in addition to time, this solution will save resources. Also, its deployment is easily manageable due to the small size of the Docker Image or the file used to run the code in the container.
5. Easier scalability and flexibility
Since Docker is built on containerization technology, it is both scalable and flexible. Now we know that each container has its own set of settings and dependencies packaged inside it, making it easier to run multiple instances of the same container. This means that deploying a Docker Image to multiple servers is very simple.
Advantages and disadvantages of using Docker
Each tool has its advantages and disadvantages. The same goes for Docker. In the rest of the article, we point out some of the advantages and disadvantages of using Docker.
1. Advantages of using Docker
- Docker can support multiple applications with different requirements and dependencies. Thus, if all these programs need the same operating system, they can be deployed on the same host.
- Using Docker, you can optimize your storage space; Because you can keep many programs on one host. This is because containers are usually small in size and take up little hard drive space.
- The container does not have an operating system, which is exactly the opposite of virtual machines, which have an OS. For this reason, containers use very little memory compared to virtual machines. In addition to making Containers more powerful, this issue reduces the boot time of several minutes for virtual machines to a few seconds. All these advantages, in addition to increasing performance, reduce costs.
2. Disadvantages of using Docker
Although using Docker does not have many disadvantages, before using it, it is good to know that applications with different operating system requirements cannot be hosted together on the same Docker Host. For example, suppose you have four programs, of which three programs use Linux and one program uses Windows. In such a situation, three applications that require a Linux operating system can be hosted on a Docker Host, But you need to put the application that needs Windows OS on a separate Docker Host.
Conclusion
If you are a software developer, you must have heard of Docker. Docker is an open-source platform designed based on the Linux operating system and can be used to create, implement, and run applications with containers. Docker and its functionality is one of the basic concepts in the field of software development and DevOps. Considering the importance of this issue, in this article from the Ded9 blog, we decided to talk to you about this platform and point out the points you need to start working with Docker.
Frequently asked questions
1. What is Docker and why is it so popular?
Docker is a source platform for quickly building, testing, and publishing your desired applications. This definition is enough to show how effective Docker can be in software development; for this reason, it is very popular.
2. What is a container?
Docker packages software into standard units called containers. Containers contain everything the software needs to run (such as libraries system tools and code).
3. What are the main uses of Docker?
Docker is an open source containerization platform that is mainly used as a software development platform for developing distributed applications that run in different environments.
4. How many containers can Docker run?
With a simple calculation, we can conclude that Docker can run about a thousand containers on a host with ten gigabytes of free hard disk available.