Lets understand Docker in 2024
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What is Docker?
Docker is a platform that enables developers to build, deploy, and run applications in containers. Containers are lightweight, portable, and self-sufficient units that package an application and all its dependencies, ensuring that it runs consistently across different computing environments.
How Docker Works
Docker uses a client-server architecture. The Docker client communicates with the Docker daemon, which does the heavy lifting of building, running, and distributing your Docker containers. Here’s a brief overview of how Docker works:
- Dockerfile: Developers write Dockerfiles, which are scripts that contain a series of instructions on how to build a Docker image. A Docker image is a lightweight, standalone, and executable package that includes everything needed to run a piece of software.
- Docker Image: Using the Dockerfile, a Docker image is created with the
docker buildcommand. Images can be stored in a Docker registry such as Docker Hub or a private registry. - Docker Container: Containers are runtime instances of Docker images. A container includes the application and its dependencies but shares the kernel of the host operating system, making it lightweight and efficient.
- Docker Registry: A service for storing and distributing Docker images. Docker Hub is the default registry where Docker images can be uploaded and shared.
Lifecycle of Containers
- Create: A container is created from a Docker image using the
docker createordocker runcommand. - Start: The container is started with the
docker startcommand. - Running: The container is now running and executing the application.
- Pause/Unpause: A running container can be paused and unpaused using
docker pauseanddocker unpause. - Stop: The container can be stopped with the
docker stopcommand. - Kill: If a container needs to be forcibly stopped, the
docker killcommand is used. - Restart: A container can be restarted using the
docker restartcommand. - Remove: Once a container is no longer needed, it can be removed using the
docker rmcommand.
Top 10 Docker Commands
- docker run [OPTIONS] IMAGE [COMMAND] [ARG…]
- Run a new container from an image.
- docker ps
- List running containers.
- docker build [OPTIONS] PATH | URL | –
- Build an image from a Dockerfile.
- docker images
- List all Docker images on the system.
- docker pull [OPTIONS] NAME[|@DIGEST]
- Pull an image from a Docker registry.
- docker push [OPTIONS] NAME[]
- Push an image to a Docker registry.
- docker exec [OPTIONS] CONTAINER COMMAND [ARG…]
- Run a command in a running container.
- docker logs [OPTIONS] CONTAINER
- Fetch the logs of a container.
- docker stop [OPTIONS] CONTAINER [CONTAINER…]
- Stop one or more running containers.
- docker rm [OPTIONS] CONTAINER [CONTAINER…]
- Remove one or more containers.
These commands provide a foundation for working with Docker, allowing you to manage images, containers, and the overall Docker environment effectively.
1) What is Docker?
Container management tool
2) How Docker works?
Docker uses resource isolation in the OS kernel to run multiple containers on the same OS. It downloads and run container images from registries.
3) Lifecycle of Containers?
Created, Running, Paused, Stopped, Deleted
4) Top 10 Docker Commands?
docker ps
docker images
docker pull
docker create
docker run
docker start
docker pause
docker unpause
docker kill
docker restart
docker rm
1. Docker is a container mgmt tool which allow to run multiple apps with less resources.
2. it make use of a dockerfile which contains the set of instructions for building a Docker Image.
A Docker Image serves as a template for creating Docker containers. It contains all the necessary code, runtime, system tools, libraries, and settings required to run a software application.
3. create -> start -> stop -> start -> restart -> pause -> unpause – > kill – > remove
4. docker create,
docker run,
docker pause
docker unpause
docker start
docker stop
docker restart
docker kill
docker rm
docker ps
What is Docker?
Docker is an platform that automates the deployment, scaling, and management of applications using containerization. It allows you to package an application with all of its dependencies into a standardized unit called a container.
How Docker Works:
Docker uses a client-server architecture.
The Docker client talks to the Docker daemon,
Docker images are read-only templates used to create containers.
Containers are runnable instances of images.
Docker registries store Docker images. Docker Hub is a public registry that anyone can use.
Lifecycle of Containers:
Create,Run, Pause/Unpause, Stop, Restart,Kill, Remove
Top 10 Docker Commands:
docker run
docker ps
docker images
docker pull
docker build
docker stop
docker rm
docker rmi
docker exec
docker logs
answer at question 1
Docker is a solution which allow you to created virtual environment – containers where different services can work on it. It allows you to created a lot virtual systems (containers) where application/microservice/service/script whatever can run inside.
answer at question 2
Docker download (pool image) and start it on local machine. Such image can be
start/stop/remove, we can login inside, we can run command inside whatever we want
answer at question 3
created;
started;
running/paused
stopped/killed
removed
answer at question 4
docker pool “image”
docker start “image”
docker stop “image”
docker pause “image”
docker rm “image”
docker container ls etc …
What is Docker?
Docker use os-level virutalization to run platform as a service applications in very simple and fast way.
How Docker works?
Docker manage containers – every container can be a different application. Container can be started/stopped/restarted/paused… in similar bur simplest way as virtual machine.
Lifecycle of Containers?
created – running – stopped – paused – killer
Top 10 Docker Commands?
What is Docker?
Docker is an open-source platform designed to automate the deployment, scaling, and management of applications using containerization. Containers are lightweight, portable, and self-sufficient units that include everything needed to run a piece of software, including the code, runtime, system tools, libraries, and settings.
How Docker works?
Docker able to operate through a client-server architecture and leverage containerization to encapsulate applications and their dependencies in isolated environments.
Lifecycle of Containers?
It involves several stages from its creation to its removal.
Create container
$ docker create –name ubuntu-cont ubuntu
Run docker container
$ docker run -itd ubuntu
$ docker run -itd –name ubuntu-cont ubuntu
Pause container
$ docker pause <container-id/name>
Unpause container
$ docker unpause <container-id/name>
Start container
$ docker start <container-id/name>
Stop container
$ docker stop <container-id/name>
Restart container
$ docker restart <container-id/name>
Kill container
$ docker kill <container-id/name>
Destroy container
$ docker rm <container-id/name>
Top 10 Docker Commands?
docker run
docker ps
docker build
docker images
docker pull
docker stop
docker start
docker rm
docker rmi
docker exec
What is Docker?
#Container management tool
How Docker works?
# The Docker daemon runs on the host operating system and manages Docker containers. It handles tasks such as building, running, and distributing containers. Once you issue commands through the Docker CLI, they communicate with the Docker daemon, enabling it to build, manage, and run Docker containers.
Lifecycle of Containers?
#5 phase :
1.Create 2. Run 3.Pause/Unpause 4. Stop 5. Kill
Top 10 Docker Commands?
# docker –version
docker search wordpress
docker pull wordpress
docker run hello-world
docker ps
docker ps -a
docker start 3ac6a4cf7b0c
docker stop 3ac6a4cf7b0c
docker restart 3ac6a4cf7b0c
docker rm 3ac6a4cf7b0c
What is Docker?
Docker is similar to virtual machine, but it’s more lightweight. Docker is using standalone containers that have got all necessary software to run applications.
How Docker works?
To run the docker first you need an image, then you can create a container. In a container you can run application.
Lifecycle of Containers?
Create, start, run, pause, unpause, stop, restart, kill, destroy
Top 10 Docker Commands?
docker images
docker ps
docker pull
docker create
docker start
docker stop
docker restart
docker pause
docker unpause
docker kill
How Docker works?
Docker’s higher level of architecture revolves around a client-server model, where the client interacts with the Docker daemon (server) to manage containers and related resources. At its core, Docker consists of three key components: the client, the daemon, and images. Client and daemon communicate using a REST API, over UNIX sockets or a network interface
Lifecycle of Containers?
Docker container lifecycle consists of five states: creation, running, paused, stopped, and killed or deleted
Top 10 Docker Commands?
1- Docker Run
2- Docker Pull
3- Docker PS
4- Docker Stop and Docker Start
5- Docker Logs
6- Docker Exec
7- Docker Build
8- Docker Images
9- Docker RMI
10- Docker Network
What is Docker?Docker is an open-source platform designed to automate the deployment, scaling, and management of applications. It achieves this through containerization, which packages an application and its dependencies into a standardized unit called a container. Containers are lightweight, portable, and ensure that the application runs consistently across different environments.
How Docker works?
Docker simplifies the process of deploying, managing, and scaling applications by using containerization. Containers ensure consistency across different environments, as they encapsulate everything needed to run an application.
Lifecycle of Containers?
Create container
Run docker container
Pause container
Unpause container
Start container
Stop container
Restart container
Kill container
Destroy container
Top 10 Docker Commands?
docker create
docker ps
docker start
docker stop
docker restart
docker pause
docker unpause
docker kill
docker rm
docker exec