![List of Docker Commands cont..
• Stop a running container
$docker stop [CONTAINER_NAME]
• Restart a running container
$docker restart [CONTAINER]
• Kill the running containers
$docker Kill [CONTAINER]](https://image.slidesharecdn.com/unitno-250428104445-fcc14f2e/85/Unit-No-III-Docker-ppt-part-2-pdf-Cloud-Microservices-Application-16-320.jpg)
![• Attach local standard input, output, and error
streams to a running container
$docker attach [CONTAINER]
• Block a container
$docker wait [CONTAINER]
• Pull an image from a registry
$docker pull [OPTIONS] NAME[:TAG]](https://image.slidesharecdn.com/unitno-250428104445-fcc14f2e/85/Unit-No-III-Docker-ppt-part-2-pdf-Cloud-Microservices-Application-17-320.jpg)
![• Push an image to a registry
$docker push [OPTIONS] NAME[:TAG]
• Run a command in a running container
$docker exec [OPTIONS] CONTAINER COMMAND
[ARG...]](https://image.slidesharecdn.com/unitno-250428104445-fcc14f2e/85/Unit-No-III-Docker-ppt-part-2-pdf-Cloud-Microservices-Application-18-320.jpg)
Unit No. III Docker ppt part 2.pdf Cloud Microservices & Application
- 2. What Is Docker? Docker is a configuration management tool that helps a developer to wrap an application and its dependencies into a Docker Container for the development and deployment of software. People and organizations have driven the demand for new applications to new heights, so the pressure is on to keep up with the demand. The task becomes easier if developers have the right tools. Docker is one such tool, a popular platform dedicated to the development, shipment, and running of applications. Today, we will look at the best way to start using Docker. But before we get into the nuts and bolts of implementation, let’s refresh our understanding of this versatile and popular platform.
- 3. What Is Docker? Cont.. • When getting started with Docker, we first need to understand Docker. Docker is an OS virtualized software platform that allows IT organizations to quickly create, deploy, and run applications in Docker containers, which have all the dependencies within them. The container itself is a very lightweight package with all the instructions and dependencies— such as frameworks, libraries, and bins— within it
- 4. Dockers place The Docker container can be moved from environment to environment very easily. In a DevOps life cycle, Docker really shines when used for deployment. When you deploy your solution, you want to guarantee that the code tested will actually work in the production environment. In addition, when you're building and testing the code, it's beneficial to have a container running the solution at those stages because you can validate your work in the same environment used for production. You can use Docker throughout multiple stages of your DevOps cycle, but it is especially valuable in the deployment stage, especially since it allows developers to use rapid deployment. In addition, the environment itself is highly portable and was designed with efficiencies that will enable you to run multiple Docker containers in a single environment, unlike traditional virtual machine environments.
- 5. Virtual Machines Vs Docker
- 6. Major difference in Docker & Virtual Machines
- 7. In the image, you’ll notice some major differences, including: • The virtual environment has a hypervisor layer, whereas Docker has a Docker engine layer. • With a virtual machine, the memory usage is very high, whereas, in a Docker environment, memory usage is very low. • In terms of performance, when you start building out a virtual machine, particularly when you have more than one virtual machine on a server, the performance becomes poorer. With Docker, the performance is always high because of the single Docker engine. • In terms of portability, virtual machines just are not ideal. They’re still dependent on the host operating system, and a lot of problems can happen when you use virtual machines for portability. In contrast, Docker was designed for portability. You can actually build solutions in a Docker container, and the solution is guaranteed to work as you have built it no matter where it’s hosted. • The boot-up time for a virtual machine is fairly slow in comparison to the boot- up time for a Docker environment, in which boot-up is almost instantaneous
- 8. Virtual machin Vs docker
- 9. Challenge's in uses of dockers • One of the other challenges of using a virtual machine is that if you have unused memory within the environment, you cannot reallocate it. If you set up an environment that has 9 gigabytes of memory, and 6 of those gigabytes are free, you cannot do anything with that unused memory. With Docker, if you have free memory, you can reallocate and reuse it across other containers used within the Docker environment. • Another challenge of virtual machines is that running multiples of them in a single environment can lead to instability and performance issues. Docker, on the other hand, is designed to run multiple containers in the same environment—it actually gets better with more containers run in that hosted single Docker engine. • Virtual machines have portability issues; the software can work on one machine, but if you move that virtual machine to another machine, suddenly some of the software won’t work, because some dependencies will not be inherited correctly. Docker is designed to be able to run across multiple environments and to be deployed easily across systems. • The boot-up time for a virtual machine is about a few minutes, in contrast to the milliseconds it takes for a Docker environment to boot up.
- 11. Advantages of Docker • As noted previously, you can do rapid deployment using Docker. The environment itself is highly portable and was designed with efficiencies that allow you to run multiple Docker containers in a single environment, unlike traditional virtual machine environments. • The configuration itself can be scripted through a language called YAML, which allows you to describe the Docker environment you want to create. This, in turn, allows you to scale your environment quickly. But probably the most critical advantage these days is security. • You have to ensure that the environment you’re running is highly secure yet highly scalable, and Docker takes security very seriously. You’ll see it as one of the key components of the agile architecture of the system you’re implementing. • Now that you know the advantages of Docker, the next thing you need to know in this getting started with docker tutorial is how it works and its components.
- 12. How Does Docker Work? • Docker works via a Docker engine that is composed of two key elements: a server and a client; and the communication between the two is via REST API. The server communicates the instructions to the client. On older Windows and Mac systems, you can take advantage of the Docker toolbox, which allows you to control the Docker engine using Compose and Kitematic.
- 13. Components of Docker • There are four components that we will discuss in this getting started with docker tutorial: • Docker client and server • Docker image • Docker registry • Docker container
- 14. List of Docker Commands
- 15. List of Docker Commands cont..
- 16. List of Docker Commands cont.. • Stop a running container $docker stop [CONTAINER_NAME] • Restart a running container $docker restart [CONTAINER] • Kill the running containers $docker Kill [CONTAINER]
- 17. • Attach local standard input, output, and error streams to a running container $docker attach [CONTAINER] • Block a container $docker wait [CONTAINER] • Pull an image from a registry $docker pull [OPTIONS] NAME[:TAG]
- 18. • Push an image to a registry $docker push [OPTIONS] NAME[:TAG] • Run a command in a running container $docker exec [OPTIONS] CONTAINER COMMAND [ARG...]