Basic Docker Notes

To run a container from an image:

1docker container run -it --rm ubuntu /bin/bash

-t: terminal inside
-i: (STDIN) grabbing
--rm: remove container automatically when process exits
--name: name the container or daemon
-d: daemonize the container running

To list all containers:

1docker container ps -a

To start or stop container:

1docker container stop container_name

To remove container(s):

1docker container rm -f $(docker container ps -aq)

-q: print only container IDs

To run a container as a daemon:

1docker container run -d --name "test-nginx" -p 8080:80 -v $(pwd):/usr/share/nginx/html:ro nginx:latest

-p: port mapping, host_port:container_port
-v: volume mounting, host_dir:container_dir
$(pwd): current working dir

To check the information of a resource(container or image or volume or network):

1docker container inspect container_name

To write a basic Dockerfile:

1FROM        #Set base image
2RUN         #Execute command in container
3ENV         #Set environment variable
4WORKDIR     #Set working directory
5VOLUME      #Create a mount point for a volume
6CMD         #Set executable for container

To build an image from Dockerfile:

1docker build -t image_name .

.: means context is the current working directory.
-t: sets a name for the image

For accessing to the docker daemon as a non-root user:

1groupadd docker
2usermod -a -G docker $USER

Remove all unused(dangling) build cache:

1docker builder prune

Rule of thumb

• 1 app = 1 container
• Process should be running in the foreground
• Keep data in volumes, not in containers
• Do not use SSH, use docker exec instead
• Avoid manual configurations inside container

Happy dockerizing, Gents! 🙂