Docker Basic Command
In this article we will discuss some basic commands of docker. If we need some basic introduction we can check the previous article (Docker: Introduction) which will be helpful to start quickly.
docker run
The docker run command is used to run a container from an image.
docker run nginx
docker run -it nginx
# creating an interactive bash shell in the container
docker run -p 127.0.0.1:80:8080/tcp ubuntu bash
#This binds port 8080 of the container to TCP port 80 on 127.0.0.1 of the host machine.
docker run --expose 80 ubuntu bash
#This exposes port 80 of the container without publishing the port to the host system’s interfaces.
docker run -v /doesnt/exist:/foo -w /foo -i -t ubuntu bash
#The -v flag mounts the current working directory into the container. When the host directory of a bind-mounted volume doesn’t exist, Docker will automatically create this directory on the host for you. In the example above, Docker will create the /doesnt/exist folder before starting your container.This will run an instance of the nginx application on the docker host. if the image is not present on the host it will go out to docker hub and pull that image down. But this is only done the first time for the subsequent executions. The same image will be reused for the next time.
docker ps
Shows the list of all running containers
docker psTo see all containers, use the -a (or --all) flag:
docker ps -adocker stop
Stop one or more running containers
docker stop [OPTIONS] CONTAINER [CONTAINER...]in options: --time , -t : Seconds to wait for stop before killing it
Here we need to pass the containers id or container name
Example:
docker stop my_containerdocker rm
Remove one or more containers
docker rm [OPTIONS] CONTAINER [CONTAINER...]
Example:
docker rm redisList the most recently created images
docker imagesList images by name and tag
docker images java
docker rmi
Remove one or more images
docker rmi [OPTIONS] IMAGE [IMAGE...]Example:
docker rmi fd484f19954f
docker rmi test1:latestdocker pull
Pull an image or a repository from a registry
docker pull [OPTIONS] NAME[:TAG|@DIGEST]
docker pull debian
docker pull debian:jessie
docker pull ubuntu:20.04docker exec
The docker exec command runs a new command in a running container.
docker exec [OPTIONS] CONTAINER COMMAND [ARG...]
Example:
docker exec -it ubuntu_bash bashdocker attach & detach
Attach local standard input, output, and error streams to a running container. Use docker attach to attach your terminal’s standard input, output, and error (or any combination of the three) to a running container using the container’s ID or name.
docker attach [OPTIONS] CONTAINER
Example:
docker run kodekloud/simple-webapp
This is a sample web application that displays a colored background. * Serving Flask app "app" (lazy loading) * Running on http://0.0.0.0:8080/ (Press CTRL+C to quit)Detach
docker run –d kodekloud/simple-webapp
a043d40f85fefa414254e4775f9336ea59e19e5cf597af5c554e0a35a1631118Attach again
docker attach a043d
Run Docker Container & gone to bash
docker run -it centos bashdocker tag
Create a tag TARGET_IMAGE that refers to SOURCE_IMAGE. By default without tag docker will pull the latest version of the image.
docker tag SOURCE_IMAGE[:TAG] TARGET_IMAGE[:TAG]
#To tag a local image with ID “0e5574283393” into the “fedora” #repository with “version1.0”:
docker tag 0e5574283393 fedora/httpd:version1.0docker inspect
Return low-level information on Docker objects. Docker inspect provides detailed information on constructs controlled by Docker. By default, docker inspect will render results in a JSON array.
docker inspect [OPTIONS] NAME|ID [NAME|ID...]
docker inspect nginxdocker logs
Fetch the logs of a container. The docker logs command batch-retrieves logs present at the time of execution.
docker logs [OPTIONS] CONTAINERdocker logs nginx
docker logs -f --until=2s test
Run Jenkins Docker with volume mapping
docker run -d -p 8585:8080 -p 50000:50000 -v C:/rakib/docker_jenkins_data:/var/jenkins_home jenkins/jenkinsReference:
